Take it to a pro shop and have them check the bow out. If everything appears to be ok, then have them watch you shoot. Maybe you're tweaking something, somehow. It's amazing what someone else can see when watching you shoot that you wouldn't notice yourself. Also, did you bump your rest or sight? What about your peep? Has it slid up or down? There are so many things that could go wrong... that is why I suggest to go to a pro shop.