1st thing is to check the bows brace height then nock height. Nock kicking up usually indicates high nocking point. But, if it is too low the fletchings will bounce off the shelf and kick high. A string will stretch and lower the bows brace height which causes the nock to shift high. Twist the string and see if the arrow flight improves. If not, you're working it too hard. Relax, take one shot at a time. Think about your form and shoot at 5 yards.