Advice ?

I'm a FTM and my son will be one in March. He was the PERFECT baby. Recently he comes up and bites me randomly. He knows it hurts me and still does it and when I pull away he'll throw himself down and scream. Sometimes he'll come up to me and just start screaming and crying so I'll hold him and he doesnt want to sit still and he'll scream to be put down. I'm pregnant again and VERY emotional lol the way hes acting is really stressing me out. Is this normal for a boy his age? I'm a ftm so not really sure what it's supposed to be like.