As I stood shivering on the landing in my thin nightie, I saw something move from the corner of my eye. Sticking out from behind a bookcase in my bedroom wall was a tail. It was in a loop, its beginning and end hidden, mercifully, behind the bookcase. And it seemed to be trying to inch it in, out of my view. I screamed and ran downstairs to the dining room, grabbed the Yellow Pages and started phoning all the 24-hour pest control firms. Only one would come, and not for an hour and a half, and it would cost pounds 120.

The first sign of rats had come the night before, when I woke to hear a strange scratching noise coming from the airing cupboard. We banged on the cupboard door a few times and then opened it. There were no furry bodies to be seen inside, but a small pile of black droppings on the corner of a sheet. My sister, who was staying with me, agreed that they were certainly bigger than mouse droppings. In fact, she said, impressed, they were even bigger than the droppings her chinchillas left.

The next day a rat man - sorry, pest control officer - was summoned. Barry the rat man assured me it was most likely the rat was just passing through and, as it had found nothing to eat, was unlikely to return. Just in case, though, he put down some poison. My warning to my three-year-old of what might happen to her if she ate this stuff on the floor of the airing cupboard was so clearly understood that she burst into tears at the mere thought.

After Barry's reassurances, I had no trouble going to sleep that night. Four hours later I was woken by what sounded like 15 children playing with the baby's activity centre, which I had used to plug a gap under the airing cupboard door. I had spent half an hour immobilised outside the cupboard, wondering if I could just go back to bed and hope they would go away, when I spotted the tail behind the bookcase and fled downstairs.

As I put the phone down our very creaky stairs creaked and I went into the hall, expecting to see my three-year-old, woken by the commotion. Instead I saw a large rat ambling down the stairs. I screamed again and found myself hopping from foot to foot in a vain attempt to get both feet off the ground at the same time. I knew if I did not get someone here immediately I would run out of the house, probably never to be seen again. Victoria over the road was summoned, arriving within minutes in her nightclothes and wellies.

Two hours later, having crawled over the whole house and found nothing more than a small pile of droppings under the bookcase, Victoria and I collapsed on to my bed. But sleep would not come and we lay there, rigid as barn doors.

The next few days were a blur of sleepless nights, rat men peering under my floorboards, removing bodies from traps, and telling me, gloomily, that I might have a family of the beasts.

For a few days all was quiet, until the burglar alarm went off in the middle of the night. The prospect of dealing with human invaders suddenly didn't seem so alarming. But, sure enough, it was the rats again. 'Someone's been tampering with your alarm,' the security man said. 'Chewed right through the wires.'

That seems to have been their last gesture of defiance. But a month on I am still hissing 'What was that?' every time a floorboard creaks. I am in the unenviable position of being able to say that having rats is infinitely worse than having burglars. At least with burglars you know they've been and gone.

I think I need a helpline, support group and counselling, but the Pest-ridden Empathy Succour and Therapy Service (Pests) does not seem to exist, and I'm too exhausted to remedy that.