My DS was born 3.5 wks ago and weighed in at 9lb 11oz. He dropped to 8.15 at his first doc visit and by 2wks he only gained back half the weight. I had issues bfing at first but saw a LC and that helped a lot. At our doc appt last week they told us to supplment with formula. Begrudgingly I did until his doc appt this week where he weighed 10.2lbs. I was so happy to go back to just BFing. However DS was not. I feel like now i just don't produce enough milk for him. He feeds for 45 min and still wants more almost every hour. I check after he gets fussy and I can't even express any milk on either side. So we revert to giving him formula. Any advice on how to get more milk and get away from the formula?