I seem to have a similar issue. I have to set 10 or so alarms to wake up for class in the morning. I feel very sorry for my poor roommate, but I don't know any other way to wake up. Luckily, I'll have my own room next year.

In fact, when I'm on break I tend to gravitate to a very weird sleep schedule where I stay up until about 7am and sleep until 3-5pm.

It seems to stem from the fact that when I go to bed at night around 11pm/midnight, I'm never tired. I just seem to be pulled toward staying up late and sleeping throughout the day. This used to keep me from getting much sleep at all, and it was drastically affecting my day to day mood and life. Melatonin has become a life-saver in this respect, but I worry about if it has any side effects or if I depend on it too much. It does allow me to be tired and fall asleep when I want to, which is WAY nicer than the alternative. I used to just lie in bed for hours before falling asleep. I wasn't on my phone or reading or doing anything productive with this time. I was just agonizingly waiting to get some sleep.