I FINISHED what I had to do and adjusted my zip. It jammed. With a certain amount of trepidation, I pulled hard and heard a ping. Pings are always bad when it comes to zips. The fastener was broken, beyond repair.

“Aaargh,” I thought. “Why didn’t I bring my jacket with me to the toilet?” The answer was obvious. Because I was in work, and I work indoors.

“Calm down,” I told myself. “Nobody will see. You’ll just walk quietly and calmly to your desk, grab your coat, casually hold it in front of you like a waiter carrying a towel and leg it into Church Street to buy a replacement pair of grey trousers.

“You will get away with this as long as you don’t do something completely stupid or unlikely to foul it up.”

I laughed at myself for my panic. Shaking my head, I turned on the tap to wash my hands. Just a little too hard. The jet rebounded off the plug and described a parabola en route to the least appropriate area of my trousers. Which, as you know, were grey.

At that point, if you had offered me unembarrassingly dry trousers with a broken zip or grey trousers with a disturbingly dark wet patch and an intact zip, I’d have taken the former. As it was, I was in the worst of all possible trouser worlds.

I stood by the door, and steeled myself for my exit . . . 

Such preamble is to explain just how uncomfortable I felt seconds before my stand-up comedy debut last week in front of an audience of strangers and people from work who had found out I was doing it.

I am not, as regular readers will readily attest, a natural comic. Nor do I exhibit a quiet and easy authority when speaking to people I do not know. Or, indeed, people I do know.

So what made me think I could stand up in front of a group of fee-paying customers and hope to amuse them?

Well, I had performed in an online comedy show in aid of Amnesty International, alongside actual comedians off of the television. “Performed” is a misleadingly chosen word.

In reality, the organiser of the show curated some of my more amusing nuggets from the social networking site Twitter and re-presented them. It required more effort from the audience than from me.

But, after the show, a few people who did not know me asked when my next actual stand-up gig was taking place. And the fear the very idea struck in my bowels made me determined to conquer it. I called in a favour, and so I found myself as the first act in the gong section of the Rawhide comedy club’s Raw show.

The music played. I shuffled onto the stage like a feckless teenage pirate forced to walk the plank. I blinked under the lights. I gripped the microphone and tentatively offered a joke I’d thought of three hours before. It got a reasonable laugh.

But that laugh was like getting a big hug from Claire Rayner in her pomp.

I started to settle down, walked around on stage. I improvised. I did silly voices. I even looked at the audience instead of my shoes. And because I settled down, the audience did, too. Everything was getting better, as things often do before they go horribly wrong.

A bell rang to signal the fact that I was halfway through my eight minutes, just as I finished a sequence. I was distracted. I looked out at the audience.

And nothing. Absolutely nothing. Couldn’t remember a word. Couldn’t even remember my own name.

For 10 painful seconds – and I know this, as I counted them – my mouth flapped like a beta-male fish trying to be served at a Mathew Street bar on a Saturday night.

The gong was a kindness when it came.

Will I do it again? You never know. I’ll tell you this, though. There’s no way I’ll be wearing grey trousers.