Explore all your options. There are a number of things that could be causing it. Rule out a sleep disorder though! Remember, in the long run, sleep disorders can shorten your life. When I had sleep apnea I was always tired. When they did sleep studies, they found that I was "REM starved." It normally takes, as I recall, a couple of hours for REM sleep to occur, but I would jump into it within 15 minutes of going to sleep. Sleep apnea would wake me up and I would not remember it, then the sleep cycle would have to start over again, screwing it all up.

I suffered from sleep apnea for several years and it triggered nocturnal seizures sometimes from lack of oxygen to the brain. Of course I didn't think my brain ran on much of anything anyway;). CPAP and me didn't get along. I finally opted for tonsil removal, which did the trick. My main problem now is meds I take keeping me awake at night and sometimes I have to take a prescription sleep aid.