Breastfeeding help. Please.

Little back story. LO is 3 days old. We have a latch problem that everyone blew off and my nipples hurt like no other. I’m going on day 7 with very minimal sleep due to early labor for so long. Last night was our first night home and she couldn’t be consoled at all even after feeding for more than 2 hours. My husband went to bed because he was tired and I’m stubborn and won’t ask for help and i ended up giving her a little of the formula we have because I’m stressed and hormonal and thought she was starving. She instantly stopped crying and slept for three hours and now I’m even more of a mess because I have her formula. I need some help please.