3 week old sleeping 4 hours a night

FTM and was waking LO every 3 hours to eat during the night, but she’s been so fussy and only sleeps on and off for an hour or less during the day, so been letting her sleep a little longer at night. During the day she’s only been BF 10 mins here, 5 mins there but then when she’s done being fussy she will eat 20 mins or so and that’s when she sleeps at night. Idk what else to do. She was fussy most of the night last night and then finally got her to feed for around 20 mins and she slept better. Any tips? I’ve tried waking her to switch sides of my breast, burping, etc. Idk what’s different but my husband started back to work last night and there was a point where my LO and I were both crying cause I couldn’t get her to settle down. I’m dreading tonight now. 😭 is it normal for their “schedule” to change? Going to try to keep her awake more today. Guess I just needed to vent.