Sleep schedule damned... need suggestions.

[Turkish]

Ok, this has been going on for the last 2 weeks. I normally can go to bed @ 12 and wake up at 8 without any problems... I am a sports person, so I exercise almost every day, and eat extremely clean...
For the last 2 weeks, I go to bed around 11:30-12 as usual and wake up around 3:30 in the morning. No matter what I try, I can't go back to sleep. I just lay under my blanket for hours and hours and I finally give up to go watch TV or something...

I seriously haven't slept for more than 4 hours in the last 2 weeks... the weird thing is, I don't feel tired. I just know its not healthy so I want to sleep like I used to...

Any suggestions? I don't really consume caffeine so I don't know what's wrong...

Anyone?