Morning, I wonder if your DD is trying to make up for a bigger need for breastmilk overnight? At 15 days we were waking DD to feed every 3 hours but that might have more to do with the jaundice.
All that sucking will be stimulating your supply :-) but sounds really exhausting. I wonder if she's actually tired and getting overtired and then fussing. The cues for tiredness are the same I'd similar to the cues for hunger.
Sit tight, it's a challenging time. Keep us the great work with bfing!!