RE: Tunig new bow
Assuming the bow is tuned well then the only thing you can do is lower your anchor, move the peep up the string (kisser also) and resight.You should be able to do as Gibblet said and gang adjust the whole sight, but you want to go up, not down.This should move your pins up also.
The other thing, about shooting low left is simply a matter of dropping your bowarm. You gotta follow through, aiming till the arrow hits the target. Part of it could be getting tired, in which case I would assume that you are drawing more weight than your body can hold up to.
Males have this problem. It's called Testosterone. They think that because they can draw a certain weight easily that they need more and more. Well, it's supposed to be easy---and fun. That's partly the reason you got into the sport in the first place. Try turning the weight down till you furthertrain the right muscles.