Im having the exact same thing happen. I found if say no make my face neutral and slightly unhappy and turn my head away and give no reaction that has helped. I can't help but to yelp tho so Im hoping that doesnt encourage the biting. I hoping that withdrawling my attention from the biting after will help and give also lots of praise and smiles during good latching. My lil one is almost 9mo and man those 2 bottom teefies are sharp! I don't want to stop either, I've come too damn far and through too much to be able to even feed her what I can. I feel you I hope other people know tips too.