What was your most embarrassing moment?

I shook violently in school when giving a talk, holding my note book, everyone could see
I was gonna draw something on the board, so I pulled the little string on the projection screen that was in front of it
It went up with a HUGE BANG
I froze, no drawing
I had half a notebook page of presentation, my friend had none
I was too nervous to utter my preplanned words

We sat back down, got detention.