Likely a gripping problem, I ran through the same thing a little bit, the other thing I found was that I had to relax my wrist on my right hand, because I was actually pulling the string out of alignment w/ the rest sometimes, resulting in erratic shooting. Get you mechanics perfect, then go through them EVERY shot. I got myself into a routine about 3yrs ago, and have shot much better every since. I found that hooking my thumb behind my neck helps me hit a consistent anchor point nearly every time.
I have to remind myself to
"Draw easy, relax your grip, loosen up your wrist,hook the thumb, steady the pin, and GENTLY squeeze, and for Christ's Sake, DON'T PUNCH that trigger anymore."