Ok, step back, and take a breath.
Now that you have changed arrow length, you have to retune your bow.
Place a piece of tape vertically on your target from top to bottom.
Start at 10 yds. Shoot at the tape until you hit the tape dead center anywhere up or down adjusting your sight if needed.
Go to 15 yds. and shoot at the tape. (Anywhere is fine, don't hit your arrows).
Go to 20 yds. shoot at the tape. (Once again anywhere on the tape).
Now, if the second shot hits a little left of the tape, and the third hits even more left, move your rest slightly to the right.
The opposite applies for the reverse.
Go to 30 yds., and make sure that your arrows are still hitting the line. If not, adjust the rest accordingly very slightly.
Now for the horizontal.
Place a piece of tape horizontally across the target.
Start at 10 yds. Shoot at the tape until you hit the center of the tape anywhere along it, adjusting your sight as needed.
Then, go to 15 yds. Shoot at the tape.
If you hit high at 15, lower your rest a slight bit, if you hit low, raise the rest....ever so slightly.
Go to 20 yds. Shoot at the tape. Make any further adjustments as needed.
This is walkback tuning. You should see a big difference in arrow flight after doing this.