Our baby is having problems staying asleep.

First time parents here, I'm the dad, the mom doesn't have a reddit account. We are dying. Our LO is 3 weeks old and over the last three days, she has slept a grand total of 10 hours.

She. Will. Not. Stay. Asleep.

She keeps giving hunger cues so we keep feeding. She is a mix of formula and breastfeeding. Mom tried to just breastfeed but her supply wasn't keeping up so we had to supplement with formula.

It usually takes about 100ml to get her to stop, sometimes that only works for about 5 minutes and then she's rooting and eating her hands and crying. We feed her again and she might take 1/4 of a bottle, then she falls asleep for somewhere between 30 and 90 minutes, then she wakes herself up/fidgets around and starts screaming.

What the hell is going on? This is a nightmare. We can't sleep. We are starting to resent her. I went back to work so mom is here with her for 9+ hours by herself in the evening. I work a 2nd shift manual labor job where I work anywhere from 8-14 hour shifts, and I do my best to stay up to let mom get some rest but sometimes I just hit the wall so hard, especially when our LO is behaving this way.

We have done EVERYTHING everyone says to do and it barely helps. She just keeps going. She is tired, her little eyes are bloodshot and she has bags. Why won't she just go to sleep?

I get that we are new at this it's just so frustrating when everyone says this is normal. This cannot be normal. Is this our new normal? This is god awful.