You asked "What is a little Low?"
*If you practice at level ground with a stationary target you do great.
*If you shoot at a live deer at thirty yards he squats and you shoot over his back. You can learn to adjust for this jump.
*If you don't practice from an elevated stand (Climber) you will shoot over his back due to the lack of gravity pulling the arrow down PLUS the deer is going to squat.
Practice Practice Practice from a climber on a 3d target if you can.

AND WEAR YOUR HARNESS!!!!