Not producing enough

Amber • Due with #3 on Feb 8th :)
I'm 6 days pp and my breasts don't feel full or hurt at all. When my milk came in they were heavy, hard and full. I'm worried that I'm not producing very much. I'm feeding him every 2-3 hours and pumping sometimes. What can I do to up my supply? Or is this normal since I'm only 6 days pp