I think the problem is your shooting till you get tired and when you shoot tired you tend to not focuse as well, and you will eventuly start to form bad shooting habits, shot till you start missing your mark, then give it a rest for an hour or so, and start over, I think you will find things starting to fall into place then. This same thing happend to me when I first started to bowhunt,,And I am sure it happend to most of the guys in here. Take you time and don't push your self to hard...Good luck, I hope that helps..