ORIGINAL: wallhangr
Been there my friend, bumped it one morning pulling my bow up. Missed the biggest buck I've had in range that day.
Moral of the story - mark your sights.
Just to add a little to what wallhangr said....Mark everything, sights, peep, rest. etc...
It does happen but these things will help you to see it before you shoot.....I have found the whiteout pens to work well with marking everything and they are easy to see!!!!