Tired about the flak over his drug-taking on the Prime Minister's plane. Contrary to last week's denials, he did snort heroin in the toilet. "So I was smacked out on the Prime Minister's jet, big deal," he told The Independent on Sunday on Friday.
Depressed because his confession to Alan Rusbridger, editor-in-chief of the Guardian and Observer and Will Hutton, editor of the Observer, where he was a star columnist, after his earlier denial, cost him his job on a paper he admired. "I confessed up to Will Hutton; there was pandemonium. Rusbridger was called in and they decided to fire me."
Angry at the hypocrisy surrounding drugs. On the Prime Minister's plane, the cabin crew went round handing out free booze to the journalists. "I feel my problems with smack are no more than anyone else's with drink. Of the hacks, snappers and microphone jockeys on that plane I would bet a percentage have a problem with alcohol."
Stressed at what the future holds. He has two children from a previous marriage and his girlfriend, Deborah Orr, a senior journalist on the Guardian, is expecting his baby.
On the flight from London to the East Midlands a week last Thursday, he went to the toilet and snorted a line of heroin along the side of the wash basin. "I confessed to Will Hutton that I'd had a bad patch with smack and ... I did take a tiny nub end of gear on the fucking flight."
It was a private thing. Nobody saw him do it, he did not upset anyone. He was not, he says, abusive or behaving oddly afterwards. He got on with the job he was hired to do, file 1,500 words for that Sunday's paper. Which he did, on time, perfectly. "At no point did I consider myself a threat. I didn't derogate from my duties. I filed my piece. I was compos mentis throughout."
He did not go on the plane with the intention of taking heroin. He was not apeing Hunter S Thompson, the American "gonzo" journalist who took drugs at a convention of US district attorneys then wrote about it.
He is not proud of what he did. This was Self, on his own, under intense pressure. "I'd recently been under stress for personal reasons and had fallen into a trough of using heroin again."
In the middle of this period he was asked by the Observer to follow the election campaign. There was a hint of what was to come. He was feeling so low that "two weeks beforehand I'd asked for time off. I was told I had to file; their whole line was that I was their star writer".
The first he knew he had been rumbled was when Simon Walters, political editor of the Express on Sunday, phoned him at home last Saturday. Walters asked if he had any comment on allegations he had been shooting up on the plane. "Walters said Mawhinney [Tory party chairman] had been informed and he [Mawhinney] has informed the police."
Self did not know what to do. "I was in a quandary. I knew I was in the wrong but I felt what was motivating him ... was envy and malice. He was political editor of the Express on Sunday; he did not have a genuine concern. I didn't feel unjustified in denying the allegation."
All sorts of thoughts raged through his head. "I knew there was no hard evidence. Someone must have spotted my physical symptoms, my pupils I suppose. But there was no hard evidence, so I decided to deny it."
Then again, he could not be sure. "At an intuitive level I realised it had to be coming from Walters. I was sure they had no proof. Well, they may have had some slight proof. There may have been a tiny quantity of smack left. I couldn't remember if I had left some behind. I thought, what has he seen? What does he know?"
With only the press at the back of the plane, "I also knew it wasn't coming from the Tories. It was coming from the press. At that point I felt entitled to reject it."
There were other considerations. "I've got two children and I didn't want them suffering. I'm separated from my former wife and I had to think of her. My current girlfriend was in the Guardian organisation and she would be affected, and she's pregnant."
Then there was the fact he had not failed to file. "I hadn't ruffled anyone's feathers. Frankly I had behaved in an exemplary fashion." He denied it and so did Hutton, who had also been called by the Express on Sunday.
"Will Hutton said 'is this true?' in his best schoolmasterly manner. I said 'no'. Hutton said, 'right, I'm going to call the editor'. He said [to the editor of the Express on Sunday] 'this is unconventional, but if you run this story I'll put a writ on you.'"
Self was relaxed about his deceit. "I'm not the Prime Minister, I'm not Neil Hamilton. I'm a hack hired because I do drugs. I was happy to deny it."
Last Monday, with rumours circulating, he met Hutton who asked him to silence the wagging tongues by signing an affidavit. Self refused. Telling a lie was one thing but telling one under oath was quite another. He was worried the paper's opponents would have a field day if he was found to have lied in an affidavit.
"I could never swear an affidavit. I couldn't drop my colleagues in it - it would have been dishonest. I wasn't prepared to perjure myself. Will said political pressures would be brought into play, that the Tories would make capital out of this. I said nonsense, I'd always been billed as a druggy writer - back in December, the Observer had put a line on its cover saying 'Will Self back on drugs again'. I couldn't be made a stalking horse in a counter-sleaze attack."
Hutton was still concerned. Self was still rebutting the charge. "I wasn't comfortable with this," says Self, "on the Monday night I left the meeting with Will Hutton, saying I was not happy - for a real reason they might have had some evidence."
Two days later, he was confronted by a Sky TV crew at his home. The Tories, he supposes, had been putting the story about.
"I realised it had broken out of all proportion. I met Will Hutton who again asked me to sign an affidavit. I said 'no'. I thought it was hypocritical of us to rebut the claim in this way. Hutton said 'yes or no'."
At that point, faced with having to sign an affidavit and not knowing if anyone had any proof, so risking heaping shame on colleagues by perjuring himself, Self confessed. Rusbridger was called and he was fired.
"Rusbridger asked 'why have you been lying to us?' I said, what you don't understand about me is that I've been living on the wrong side of the law since my teens. They marketed me in this way but they don't understand me. There is a colossal hypocrisy at every level. When push came to shove, they wanted to draw any taint."
Their sensitivity, he says, underlies everything that is wrong with the election. "There is a prevailing morality which dominates this election campaign. I don't want to attack the Guardian/Observer newspapers because I do think their campaign about financial corruption is correct, but I do abjure to the anti-libertarian tone which says you must behave in a certain way."
The same politicians and papers that accuse him of taking drugs also condone their people smoking and slugging alcohol on the campaign. "Unlike most other internal flights, 11 rows at the back were dedicated to smoking. Stewardesses were standing with loaded trays of whiskies, Bloody Marys, gins and tonics."
He has not taken drugs in the newspaper's offices, he says, and this was his only time on the Prime Minister's plane. He was not scared, he did not get a buzz out of doing drugs surrounded by Special Branch. He needed a shot of heroin. Pure and simple.
Self does not think he needs rehabilitation. "Without being arrogant, I do think I'm an exceptional person like that. But my hubris brought me down. My hubris led me to this, because I knew I could file. I don't think it's clever - I've dragged people I'm close to into deep shit."