My most embarrassing moment was when I was 15. I was sleeping over at my best friend's house, and after eating plenty of chips and sweets and stuff I went to bed feeling a little sick. I fell asleep very quickly. When I woke up the next morning, the first thing I saw was my friend's dog licking something on me.
I looked down and it was DIARRHEA! I had been so sick that in the middle of the night all those chips and sweets had come out in a very unattractive way! Now my friend was sitting there looking embarrassed - but not nearly as embarrassed as I was - and her brothers and sisters were running around shouting "Ewww! She pooed in her pants!"
My friend moved away that summer (not because of me!), so fortunately I was spared the embarrassement of having to face her again.