I can't sleep and I have 2 exams in the morning...HELP?

I'm a college student. I've been trying to fall asleep for the past 3 hours. I've been laying in bed, in the dark, in silence. Tried counting sheep, tried breathing exercises, I FEEL LIKE I'VE TRIED EVERYTHING! I have 2 huge tests tomorrow, the first one is at 9. Should I even bother trying to get 4 hours of sleep at this point, or just pull an all-nighter?