Oh, it does hurt, doesn't it?!? My DS started to do it at that age too because of teething. He did it mostly while still latched on, but sometimes after pulling off as well. I started to watch him very closely throughout the nursing session and started to pick up the different behaviors that let me know he was likely going to bite. He'd adjust his latch a bit, obviously to pull his tongue out of the way in order to bite. And he'd come on a little differently too, and I knew a bite was coming. I always had my pinky ready and slipped it in as soon as I saw the switch, to prevent him from biting. I'd pull him off, take a little break and then start again. After a couple days of doing that really consistently, he'd stop biting. We went through this at about 5.5 mo and 7/8 mo, both times while teething. Also, keep giving the chance to chew all day long on other things like you're doing.
