I had this at Uni last year, and I fell into a f**king horrible routine which led to me missing lectures and work. Was an awful place to be, but you seem to be getting up fine, i just used to sleep through the day.
The way I get tired now is reading in bed, it's amazing. After around 40 mins reading my eyes just start to droop and I fall asleep. I presumed you do this anyway as I noticed your kindle next to your bed.