So much for training
Was lying on the couch and foster pup (maybe) was lying on my chest nibbling my ear lobe. She got a bit carried away and champed down hard with those little needle teeth. I yelled Ouch thinking it would let her know she'd gone too far but she just took a step back, sat down, looked me in the eye and barked. I had to laugh at this bossy wee puppy (3 lbs.). Ouch doesn't seem to have much impact so in future will just put her down.