It is fitting that the sequel to the film Trainspotting, which revisits the characters 20 years later, has its world premiere just days after Donald Trump is sworn in as US president this month. For the original film, and Irvine Welsh's 1993 novel on which it is based, is like a snapshot of the social, cultural and economic forces that made Trump possible, just as they gave rise to Brexit.

I was working as an usher at a cinema in 1996, and remember Trainspotting well. Partly this is because I saw the film, or at least snatches of it, a hundred times. But I also remember the film because I was vomited on – not once but twice – during the months it played at the cinema. People were always walking out of Trainspotting, either affronted or queasy or both, and on two separate occasions I opened the door, like a good usher, only to be hit by the flying spew of someone who'd misjudged the timing of their exit.

The characters of Trainspotting: Spud, Renton, Sick Boy and Begbie.

Being vomited on while doing a low-paid casual job struck me at the time as a very Trainspotting thing to have happen to you. But it wasn't the only reason I related to the film, even though I'd never taken heroin (or in fact anything stronger than marijuana) in my life. Trainspotting is a film about drugs, but more than that it is a film about feeling lost, about going nowhere and about the narrowing of opportunity.

I couldn't help but relate to this in mid-'90s Australia, even if I was tertiary educated (like most of my fellow ushers) and middle class, and my immediate concern was not how to score heroin, but how to get vomit out of an usher's standard issue velour waistcoat.