Hmm, ice cubes or water usually work.
Nah, I used to be like that when I was in school/college.
But I guess it was mainly because I was plain lazy and didn't want to get up, I'd turn my alarm off and go back to sleep, then my mum would call me and come in my room and I'd fall back asleep, but I'd tell her I'm up and doze off.
And now, I'm up past 5:00AM usually every night because I can't sleep, so I stay online, and go to bed just as I'm about to doze off.
But I am such a light sleeper now that when I hear a creak or any tiny tap, I'm up.
And I wake up in the morning when my mum call's me.
I don't know what happened there.
It could also be because I have changed my eating habits, where as back then in school/college, I was eating junk.
Oh, and when I was living in the stable for 6 months, I'd be in bed till 3:00PM and nothing could wake me.
Weird though that you don't know what you are doing, I don't know what that is, but yeah, like northernmama said, talk to your doctor about it, get some advice.