Colin was a zombie movie told from the point of view of the guy turning into a zombie. Made headlines at the time because the guys that created it only spent 220£. I believe it was only shown at a film festive, but crappy copies are to be found online.
I remember liking it at the time, and it has a great ending! Not sure how it would hold up, but I finally found a watchable copy.
It’s called “growing up”.