I shot in my bow to dead on at 20 yards with field tips.

I got up aout 13 feet high and shot sets of 3 arrows at a target 6-7 feet away.

1) 1st shot, tried my 20 yard pin and aimed 3 inches low on the 3 inch center cirlce. I struck 2 inches low.

2) 2nd shot, I tried my 30 yard pin and aimed for dead center, I hit 3 inches high.

3) Shots 3,4,5,6...I used my 20 yard pin, aimed at the center of the three inch circle, and all 4 arrows struck in the middle 3 inch circle.

A couple of things about my bow. I use a drop away arrow rest. I do not use a peep sight. I use an anchor point in the corner of my mouth and let the string touch my nose for my second anchor point.

Not really sure why I am able to hit good using the method I do, because it seems everyone else uses their 40 yard pin on such tight shots?

Any thoughts on why this is happening to me? Maybe my arrow rest if not positioned correctly at full draw? Thanks for any insight.