I am so Tired

I've slept six hours total, during the past three days. I go to bed at 8 p.m., knowing I have to get up at four a.m., but all I do is lay there. My mind just races. I think about everything, nothign really. My hands are like, starting to shake from lack of sleep. The worst thing is I'll be exhausted all day, and the moment I hit the bed it's like I get a sudden burst of energy.
I keep myself going somehow.