It didn’t really happen to me but I was there at the time.
As kids a group of us used to play in a derelict old pub - actually I may post a spooky experience one of our group had in there.
The top storey of the of the pub had a huge room with a fireplace at either end, and we used those fireplaces as goals for a game of five-a-side football - but using a tennis ball instead of a normal sized ball.
The pub was in a very bad state of disrepair, missing floorboards, large gaping holes in the roof, and sharp electrical wires hanging from parts of the ceiling.
After school one evening, we were up there mucking around as usual, when the floorboards gave way in a part of the room we were playing in.
One of our crowd fell right through the floorboards landing in the room below, unfortunately those floorboards also gave way, which sent our mate crashing down and landing onto the stone floor of what was the pubs main bar area.
Off we went running down two flights of old stairs, which were shaking and threatening to come away from the wall, and when we got down there we could see him lying in a heap in the corner of the room.
We gently turned him over so he was laying on his back, and called his name a few times, and after a few seconds we saw his eyes flicker and then fully open – I can’t begin to tell you of the relief we felt that he was alive.
We picked him and brushed him down, but apart from being filthy dirty with dust and goodness knows what else, he was absolutely fine, not even a scratch the lucky sod – for many years after, his nickname amongst our group was the fall guy lol