I've never been the sort of person who looks at life, or myself, through rose-coloured glasses.

But I do appreciate it when I tell someone my age and they affect surprise and tell me I must be joking.

I wasn't too happy, it's true, when a colleague blurted out, "I didn't think you were THAT old!" on my birthday a few years ago but, back handed compliments aside, I've come to enjoy being told my birth certificate is obviously lying.

Unfortunately, an incident this week made me realise I've been living in a fools' (or old fools') paradise.

Now one of the benefits of working for and by yourself - apart from the downside of being poor and lonely - is that you can take the day off, quite legitimately, any time you choose.

So when a friend, who was having a week's holiday from work proper (ie a wage slave), rang me and suggested going to the afternoon showing of a film we both wanted to see, there was no need to concoct excuses explaining my absence from my desk.

You know the sort of thing - you're taking the dog to be neutered, your hernia's strangulated or some ancient relative has shuffled off this mortal coil.

Just before leaving my house I glanced at the day's Argus and noticed the performance we wanted to catch was a special showing for pensioner folk. Damn.

I called the cinema, explained that my friend and I were not OAPs but was told this didn't matter.

"There are no age restrictions," said the voice. "It's just pensioners attending this afternoon's show get a free cup of tea and a biscuit."

How nice, I thought. What with bus passes, £200 towards your fuel bills and free TV licences, it's almost worth acquiring those white hairs.

When I arrived at the cinema my friend had already bought the tickets and refused my offer of payment.

"Would you like an ice cream, some sweets, popcorn - my contribution?" I offered.

"No," she said, "but a cup of tea would be nice."

I went to the counter where sweets and drinks were being sold and ordered two teas, searching in my handbag for my purse.

The girl behind the counter, who looked about 16, handed me the teas and before I could hand her my money had turned to the next customer.

"Excuse me," I said, clutching my coins.

"Oh, sorry," said the girl. "The free biscuits will be coming in a minute."

I was speechless, scarcely able to splutter, in itself a rare event.

"Let's have the tea then, gran," a voice from behind me said. My friend, who is five years my junior, was grinning, clearly enjoying my discomfiture.

Noting my sour expression she tried to make amends. "Never mind," she said.

"The light's not very good in here and anyway the girl's busy, she probably didn't get the chance to look at you properly."

Then she noticed the biscuits had been put out. "After all that, aren't you going to get some?" she asked. When I declined, she went for a few herself.

"Sorry," I heard the girl behind the counter tell her, "I'm afraid you can't have one - you're too young! Biscuits are only for our elderly customers."