I'm a first time mommy and have no idea what I'm doing.

Lately, my son has been screaming, at the top of his lungs. All. The. Time. When he is out of food, wants picked up, put down, doesnt get what he wants, etc. He was doing SO well with saying the actual words, and then out of nowhere switched to this.

He also bites. 99% of the time, it's me and not anyone else. For that reason, I've been told it could be a way of suckling to soothe. Anyways, he obviously has teeth and leaves bruises. His pediatrician told me to flick his cheek (he just bites harder) or to try crying and telling him it hurts mommy (he laughs). I've tried waiting until he unattached and firmly telling him no, moving away from him, and even patting him on the butt when he does it (which also makes him bite harder, and I've never been super comfortable with spanking, anyways). Does anyone have any experience or advice on either topic? I'd really appreciate it.