What is this? Has he sighted my doppelganger hanging out on the King's Road, pinching my parking meters on her way to buy light bulbs?

I arrive at a central London salon to get my hair cut. Except the receptionist tells me thatmy appointment was cancelled earlier that morning. By me.

"What?"

She glances down, long vanilla hair tickling the page, rests her ballpoint next to Thursday. "You rang and cancelled.About an hour ago. Weird, eh?"

"I can't believe it - someone actually gave you my name?"

She nods. "Oh definitely. Julie Myerson."

"I can't believe it."

"So it wasn't you?"

"Absolutely not."

She frowns, loops pale strands of hair behind her perfect ear. "Well, unless I misheard. The trouble is, Estelle's not free anymore. You could have Jethro in 10 minutes."

I opt for Jethro and sit there wondering what to feel. It's not the inconvenience - which is, after all only slight; it's the invasion. Appointments are personal, carefully calibrated things, which define the tone of your whole day. Mine have just been invaded, ravished, spoilt.

"Maybe you have a clone," laughs the tall man with cheekbones and a wisp of a ponytail. He blots my wet hair with a towel. "Or a lookalike. Like those people who make a packet being Princess Di or Madonna."

I don't think so.

Still uneasy, but divested of my split ends, I stop off at Peter Jones for some bathroom light bulbs. I park on a street with black wrought iron railings and clean, magnolia-coloured pavements. But when I push a coin into the meter, it doesn't register. I try another. Same problem.

There's an olive-suited attendant close by so I call him over and politely demand help. "You pushed the coin in too slowly,'' he says.

"Too slowly?"

"It's very sensitive."

"But I pushed it in quite quickly, look," I flick my thumb into the air to demonstrate.

"Well," he blinks a perfect, replicant blink, "you pushed too quickly then."

"Look," I tell him, on the verge of laughing, "I pushed it at just the same speed as I usually do, a totally normal speed - there's not much possibility of variation. It's just a coin going into a slot isn't it?"

He sighs, blinks again: "It's electronic - very sensitive."

So am I. And short of time. "Try another one," he says.

"I don't want to lose another coin."

"I don't think you will - go on."

I shove in a 20p piece (deliberately, sluttishly careless about the speed) - and it registers. Another one does the same. "You see?" he almost skips with delight, "It's working now. You were just a bit rough with it."

"So can you give me a refund for the money I lost?"

Immediately, he regains his robotic impassivity. "Sorry. Not allowed to do that." He congratulates the meter with a furtive glance, then adds shyly: "Haven't I seen you before? You ever on the TV?"

"Never," I mutter darkly. What is this? Has he, too, sighted my doppelganger hanging out on the King's Road, pinching my parking meters, on her way to buy up all the 40-watt Edison screw light bulbs in Peter Jones's lighting department?

"You're sure?" - he grins, folds his arms. He thinks I'm being modest.

"Perfectly sure."

"You've got one of those faces, haven't you?"

I get home to find a letter from Burke's Peerage on the mat. "Dear Mr and Mrs Myerson, I have exciting news for you and fellow Myersons! I have been working on a project relating to your Myerson family name. Finally, after years of effort and considerable expense, we are ready to publish The Burke's Peerage World Book of Myersons, and you, Mr and Mrs Jonathan Myerson, are listed in it!" The letter is from a Mr Harold B Brooks Baker.

Attached to the letter are two colour photos: one of Mr Brooks Baker himself, smug and rigid as a waxwork behind his desk, in front of a backdrop of Burke's Peerage books. The lips are tight, unsmiling, the suit soberly black. The word "undertaker" springs to mind. He appears to be fiddling with a paperclip.

The other snap is of a Happy Family - blonde Mum in Persil whites, repulsively Brylcreemed Dad, two nerdy kids - grinning rapturously at (presumably) their own Burke's Peerage World Book of ... The setting is, naturally, fake baronial: leaded windows, coat of arms on a porcelain plate, snobbishly polished table.

"Don't you want your own Book of Myersons?" Jonathan says. "You could phone to cancel all their hair appointments,"

"I just wish I knew who it was," I persist. "I hate mysteries." (A lie - I adore them.)

"There's no mystery. The receptionist has a hearing problem, that's all. "

"And the parking-meter man, thinking he'd seen me?"

"Coincidence." Jonathan shows me an article in today's paper which says that coincidences are - and should be - far more rife than scientists originally thought. It appears that their original calculations were wrong. "And you've probably got that kind of face."

Clearly, I have. On Sunday morning, the little ones and I go to the Odeon, Leicester Square, to collect Jacob and his best friend from a special screening of Free Willy 2.

It's a scorching morning and we're early. The plump doorman - pouring sweat in his grey suit - says helpfully that I can leave the pushchair downstairs with him while the kids and I go up and wait by the coffee bar.

As we start to climb the air-conditioned, popcorn-strewn stairs, he suddenly calls me back: "Hey, Miss!"

"Yes?"

"I know you, don't I? You're on the TV."

I open my mouth to disabuse him, but he holds up a finger: "Wait! Don't tell me, I've got it: Bianca!"

"What?"

"You're Bianca in EastEnders, aren't you?"