[Her Name Is Rio]

I've had Bullet for almost 3 weeks now and he's developed quite a habit of biting my hands/fingers. I've tried telling him "NO" firmly, I've tried giving him a toy to bite (but he tries to bite my hand that is holding the toy), I've tried yelping/crying like a dog to tell him it hurts but he won't stop biting! It's a playful bite, not an aggressive bite but he tends to hold on once he's gotten a good grip. I think he's teething too (he'll be 16 weeks this Friday).

Any suggestions on what else I can do to stop his biting? I'm afraid he's going to draw blood!