Long post ahead! Sorry!

Baby is 3 weeks 5 days. I really don't know what to do. I'm exhausted mentally and physically. My baby has so far been really content and even tempered. She's not a crier at all but today has been rough. She's not been napping well (only 45-75 min) and whenever she wakes up she's screaming like she's starving. I'll go to nurse and she'll latch for a few minutes then pull off and scream. I've tried burping her every time she pulls off, because that's what she had been doing when she needed to burp (minus the screaming) but that only seems to make it worse and she hasn't really been burping. Today has been the day from hell. I feel like she hasn't gotten a full feeding or a full nap. She's obviously exhausted and I think she's hungry but she'll only feed for a few minutes before screaming. I'll get her calmed down and try to get her to start nursing again but she just screams louder. I don't think this is cluster feeding since it doesn't seem like she's eating enough to drain my breasts. She'll pull off and I'll be leaking milk everywhere. Is this a growth spurt or has she turned the witching hour into an entire day? Her temp was 98.8 at 6 PM but has gone down to 97.9 at 9:45 PM. I've tried gripe water (which worked for 5 mins before she started screaming again), baby wearing, tummy time, cuddling, and just about anything I can think of. I'm about to lose it. I feel awful for not being able to help her and I feel like she's probably starving but something is wrong that she won't eat. Please help!