No milk?

I'm trying to breastfeed. We were having issues in the beginning and were told to supplement. She would nurse and was still hungry. Decided I would pump only and do 1 oz breast and then 1 oz formula. Well, the formula was helping her gain weight but it upsets her tummy. A lot. Well, pumping only supply has started dwindling. Was told by pediatrician that to keep supply up she needs to nurse. Started nursing again but she's a lazy feeder and will start and go to sleep. I also need to use a shield. My nipples aren't large enough and, again, she's lazy. But when I pump after she eats I'm not getting much of anything which means after her feeding I have nothing to give her to help keep her full and I have no clue what she's getting if anything when she nurses. I know I need to eat and drink lots of water. I'm going through at least 64 oz a day, if not more and nothing. What the hell can I do to make more? I feel like I'm failing and Ifind myself  blaming my daughter and I'm really starting to resent her. She'll sit there and scream her head off after feeding, still hungry and I just want to scream at her! I mean, it's not my fault she won't eat and then she sits there and complains that she's not getting enough 😩