My dog is being very protective over me and she lays her head on my stomach is that normal?

Yes...

Yep she knows there is a baby in there and she is protecting both of you

Cause she will snap at people if they get to close or if they try to move to fast when giving me a hug or something

Yes

She jus smells the baby

Yep that’s how my SILs dog was with me. She wouldn’t even let my husband touch me lol

My cats were the same way lol