I need Help... breastfeeding/breast reduction/formula


Ok so I’m a FTM and this may seem dumb but I need help...

My baby girl is a month old and we still have yet to figure this eating thing out. I had a breast reduction 10 years ago, so my feeling isn’t completely there... because of this the hospital didn’t really give us a good chance to breastfeed before giving her formula. I want to breastfeed!! But I’m afraid I don’t produce enough for her. So we were breastfeeding and supplementing with formula... then We’ve tried going on just formula and her reflux is so bad that now the dr wants us to strictly breastfeed. So now we are just breast feeding and I don’t think she gets full. She is constantly on a boob... my mom asked me if I feel my let downs because that should help me know that she’s eating, I don’t feel them.... on Friday she weighed 8.7 and on Monday she weighed 8.6..... I’m scared to death that I’m doing something wrong... please I’ll take any advice!!