Sleeping patterns are so difficult to control. It's true that the sooner you go to bed, the sooner you'll wake up. Maybe you should try to do a relaxation before getting asleep (even if you are tired enough to sleep, like a way to empty your mind of absolutely everything?)

I have a couple of very good relaxation methods (if you manage to get to the end of them, I mean, I usually get asleep before reaching the middle *lol*) The best one is setting your mind on a landscape you've visit and take notice of everything you see (even the smaller leaf) or simply staring to a white sheet of paper (I use this one when I'm very stressed and it works marvels)