7 month old-biting?

Rinny22

My 7 month old has two lower teeth and is getting his first upper.  He has occassionaly bit me in the past while nursing, but lately it's becoming much more frequent...he's drawn blood!!  Ouch!

My instincual response is to pull away and yell...when this first started happening, he would cry a little, but now he laughs...I don't know what else to do, but I have got to find a way for him to stop doing this!  Any advice, or tips?

TIA