Help!

Ariel • BFP on 8/4/14 had a beautiful babygirl 3/8/15
My little girl is 4 months and I feel so moody still. I can be perfectly happy one moment and one little thing will make me mad. I feel like I'm going crazy. I'm constantly in a bad mood. Is this normal after a baby? I don't want to put a strain on my marriage when I've just gotten married!