I have a question about draw length. I did a search but the posts didn't answer my questions excatly, so here's my questions.

#1 what is the valley exactly ?
#2 what does the valley feel like ?if you draw is a little two short or two long ?
#3 sometimes when I shoot if I relax just a bit I feel the cams move and I have to pull back into place a little, Is this the valley ? does this mean my draw is two long or short ?