Probably the most embarrassing thing ever for me was when I was on a swing and I managed to get tangled up, flipped upside down, and my pants came down so I was dangling there in my boxers. xD Even at the time I killed myself laughing though so maybe it wasn't that bad?

Most embarrassing thing nobody ever saw was braining myself with half a brick, something I've related elsewhere on this forum.

Also I managed to smash the same fingertip in the same contraption like four times when I was a kid. Pretty dumb and I don't know how sheer shame of making the same mistake twice didn't stop it from being made twice more.