The things you find online. This is my school photograph from thirty years ago and if you’re now peering to see which one is me, imagine how I felt coming across it this week on Facebook. By accident.

I don’t remember the day this was taken but I do very clearly, very physically remember this photograph: the copy I got then was a print in a brown cardboard sleeve. Seeing this shot online, that was my first reaction. Surprise came second, looking for me came third, I was hit first by the feel of that old print in my hands.

I do remember that on this day or one around it, the headmaster in the front row did some speech or other in which he said there was a song that summed up how we must all be feeling as we reached the end of our school days. He was a very hip headmaster so it was probably something like The Old Rugged Cross.

But I do recall turning to whoever was next to me and – in a display of contemporary pop music unusual for me at the time and unheard of since – whispering that he must mean Captain Sensible and Glad It’s All Over.

Can’t remember who I said it to. I look at this photo and I can name just ten and a half people. It wasn’t a great school, I wasn’t a great pupil, all it really did was knock a child’s automatic respect for authority out of me. I remember my chemistry teacher spending a whole lesson on getting us to mark another class’s homework. He stood at the top of the lab and said what the right answers were supposed to be while we were meant to tick or cross and report back the final score. I’ve no idea whose exercise book I marked, I don’t remember now and I didn’t care then, I just went straight to the end and gave the kid 10/10. What was that teacher going to do about it?

Another teacher did try something on: he worked hard to get me thrown out. I worked harder to stay in. I won. It was an entirely unwarranted move on his part, he was actually heading for a breakdown and was causing much damage to perhaps one kid per class year. But it was the first time I remember where I had to get really political, to think around and over someone playing the rules against me.

Oooh, it’s all coming back. That politics did help me in journalism, I’ll give the school that. But the last thing I remember about the place was how wrong the careers advice was. If I could figure out the name of the careers teacher who laughed in my face about my becoming a writer, I would not be above going back to him now. But I’m drawing a complete blank.

Blank on him, blank on all the teachers in that photo, blank on so many more people in there. I do remember who I fancied. I hadn’t remembered quite how many there were. That’s embarrassing now. I expect it was embarrassing then, too.

I only remember asking one woman out, I’m certain I didn’t actually go with any one there. Nobody in that picture. Grief, I hope I’m right about that. Or at least, if I’m wrong, that she isn’t reading this.

What are the odds, though? I sent a copy of this photo to one of maybe two and a half people in it that I still know. Jim McCarthy: second row of pupils from the back, right hand side of the photo, standing between Thingy and Er.

Jim is much better at remembering everyone, he really put me to shame there. But he also vocalised something I hadn’t realised I was thinking: the fact that whether or not you can name any face in that shot, we ourselves are unrecognisable. Or rather, we are unrecognisable to ourselves. I look at me there and I’m alien. Lifetimes and worlds ago. I prefer the me of today to the me of then. I know that the me of then would be very happy with where I’d ended up so far, but I hope he would also have told me to bloody well get there faster than I did.

I hope so, but I’m guessing. I don’t know that William Gallagher any better than I know Thingy, Er, and Whatsherface.

After I found me in that shot, after I found Jim, after I got bored trying to recognise many others, I did find Whatsherface, the woman I remember asking out. That was so strange: an instant, a picosecond before I found her, I thought of her and expected to feel – I don’t know, rejected of course, probably daft. I did like her enough at the time that she would make me tongue-tied. If anyone in that shot remembers me as an eejit, well, hey, it’s nice to be remembered and it’s impressive that they remember me so accurately. She cannot remember me accurately because I was entirely a different kind of eejit in front of her. It’s not really a difference that makes much difference, but it makes much difference to me.

Only, even if she knew me as eejit, it was also a pretty shallow kind of knowledge. She didn’t know me well, I didn’t know her well. It was a pretty temporary knowledge too: I am not the boy I was. Doubtlessly she’s not the woman she was. So here’s someone I didn’t know then and I don’t know now, but she’s fixed in my head as the 17-year-old she was in that photo.

Lots of writers swear by the idea of creating the young character in their heads before begin writing. What music did they like, what posters did they have on their wall, who did they have a crush on, what was their best subject. I have always found this notion stupefying and believed it only an excuse to postpone writing. Ask me after I’ve done a script and I can probably answer all those questions immediately: I know the characters so well by then. But at the start, I’ve not a clue and I have never believed that it tells me anything.

I suspect now that I believe this because I unthinkingly knew of this schism between the me of then and the me of today. I get the whole nature vs nurture argument, I know you’re thinking that the me of today was formed by the me back then, but it feels like I have several walls between the two of me.

I’m happy being this side of them all. But just for a moment, it was nice to peek back.