Questions:
1) When you fall asleep, the amount of sleep that you are getting, is it your normal amount (IE: Bob sleeps 8 hours every time he goes to sleep) or; Are you waking up at your normal time (IE: Bob always wakes up at 8am regardless of things)?
2) When you wake, do you feel exhausted and/or tired, but are unable to go back to sleep (or back to sleep easily) if you wanted to or; When you wake, do you feel like your normal self and proceed through your day as if you had your normal sleep routine? (Mind you, this does not mean a good thing. Eventually you will tire out.)
There are times when something is going on in your life that is stressing you out. That will play a factor, as others have mentioned. Those types of questions I'm not going to ask.
Drugs and alcohol are not really recommended though personally, trying them out once or twice at the most, may be enough to set you straight. Another option is to stay up until the next evening. For obvious reasons, do this when tomorrow is your day off and cancel any plans you had. Most importantly, don't take a nap. Do yard work, rearrange your nest (I did that recently, found 20 dollars.

), etc. Then go to sleep at your usual time.