I can't sleep.

I'm not a very good sleeper. I didn't get home until 3 am this morning and I'm wide awake at 7. It's annoying really. I need to sleep and I can't. I don't know why sleeping is so difficult for me. I have no problem falling asleep, staying asleep is where I struggle. I'm not thinking about anything, so it's not those damn voices keeping me up. Emmitt was sleeping soundly, so it's not him. My bed is really comfortable, so it's not that. It's relatively quiet here, so it's not the noise. My room is pretty dark, so it's not because there's too much light. Hmmmm...I'm out of ideas.