Yo you're not fucked in the head cause of that I was the same.
the only way id go to sleep early was by drinking and smoking, wouldn't even call it going to sleep...passing out seems more appropriate.
Otherwise just like you id sleep at 5 am and wake up at 3 and then have my system screw me over.
but seriously just wake up early,,, even if youfall asleep at 5, wake up at 12 max, next day wake up at 11 max, and so on till you wake up at 9.. you'll be readjusted I can almost promise.
goodluck