When you're sitting on the bench at school and you think you pissed yourself, but you're not sure... When you try to look, you can't because you're wearing black pants. Then when you try to feel your pants, you can't because your hands are numb. Then ultimately having to ask someone if you pissed yourself, then getting weird looks.
When you buy donuts, then drop them all on the floor, then pick them all up and eat them right there in the diner, still standing in front of the counter.
When you drive to another city for something to eat, only to decide that you're not that hungry any more and turn back, then half way back decide again that the McDonalds over there did look pretty good.