I got a new puppy he's about 10weeks and he is a shih tzu. I have a 3year old black lab (female) my new pup (male). I intrudcused them to each other carefully and then my lab started to push him around with her head, she was laying down then with her neck pushing the puppy down on his back to make him lay down with pressure of her neck, I don't know if she was biteing or what but she was trying to pick him up by his neck. I really want to play with both and non to get jellious so them both to get along. I heard that labs take instant mother to a puppy. Please help!!! Tips?