When I was a kid, I was playing with some friends who had managed to get a big plank of wood up into a tree, balanced on just two branches.

I climbed up onto it and walked out onto the board between the two branches and it predictably collapsed. I fell, landed on my feet, and the board landed in front of me completely vertically. My nose went down onto it completely and hit hard.

Had a nosebleed for several hours. Was not a good time, but I can look back and laugh now.