If you were shooting well enough before, changing equipment was probably not the solution, in the first place.
Something that could help is to get in front of a large target butt (one you can't miss). Get close to the butt (5 yds. or so) and shoot with your eyes closed for a while. Just get oriented enough to keep your arrows on the butt and don't worry about aiming. Concentrate on your form (bow arm, anchor, stance) and how the shot feels. This method tends to get you more in tune with how a good shot feels and will carry over when you start shooting normally. After doing this for a little while, turn a target backwards, or just use a blank piece of paper (no bullseye), and fasten it to the butt. Back up to 10-20 yds. and aim for the center of the paper. Do this for a while, concentrating only on center mass and how the shot feels.
When you start to feel more confident, put up your bullseye target and see how it goes. If the problem persists, go back to square one.
Don't worry if it takes a while, just keep at it. This is something most of us go through, to some extent, at one time or another. Sometimes you can get over it in a couple of hours, sometimes it takes a lot longer but, if you keep at it you'll be O.K.
As for punching your release, just work on a good smooth pull that is comfortable to you. Finger placement isn't important, as long as it is consistant. I like to hook my finger on the trigger and use shoulder tension/back pressure to trigger the release but, that's something you can work on after you get your confidence back.
Good luck.