Not producing enough milk!

So my son is 6 days old and I'm a ftm and my breast are becoming firmer and bigger but my left side isn't producing as much as my right and I don't know how to make it produce more. My son feeds a lot and because my left side isn't producing enough he'll eat me dry on that side and because he's still hungry I've been having to give him formula which I really really don't want to do. I've been pumping but it doesn't seem to be doing much and I'm getting down about it.. I just want to produce a good amount for my son so I don't need to give him formula.. Any advice would be great!!