This is pretty funny, in a tragic sort of way.
I was locked in a toilet once, a few years ago. I was at a housewarming party at this huge house in London, but some of the building works hadn't quite been finished. I went to use the bathroom but someone was in there, so I decided to head upstairs to find another instead. I found one, and pulled the door shut behind me, and then realised there was no handle. I tried to open the door again, but it was totally impossible from the inside. I stood for about five minutes wondering what to do and then I heard someone outside and I shouted for them to come and open the door, and they did. Hardly 16 hours, but it still sucked.