Does she have her days and nights mixed up?

tlong

For the past few nights DD has been up every 2 hours and last night was up fussing/eating from 3am-6am. She always seems famished at night. However, during the day, she sleeps 3-4 hours stretches and I often have to wake her around the 4 hour point to eat. She's a preemie so she sleeps a TON but it seems like she sleeps longer stretches and sounder during the day. Do you think maybe she is eating all night and then sleeping all day instead of doing the opposite? I am attempting to wake her every 2-3 hours today to see if that changes anything for tonight. Anyone else in the same boat?