Waking Up In The Middle Of The Night!....and not going back to sleep for hours!!

Okay, who can tell me why we sometimes wake up in the middle of the night and then we're unable to go back to sleep. So, we solve "the problems of the world": Call her. Email him. Set up that meeting. Cancel that meeting. What was his/her name? Oh, come on, I should know that. (Oh, NO! Am I beginning to lose it?) Call Robin and get a good, easy cookie recipe. Today FOR SURE I'm going to straighten up those files. Water the plants. Write that report. Call 1, 2, 3,.... (At that point, I get the flashlight, open the side table drawer, take out the pad with the pen attached, and make notes.) Maybe if I write these down, I can put my mind at ease and go back to sleep.
Now that that's done, I'm going back to sleep. Oh, wait, I forgot about that phone call. Okay, I'll call first thing tomorrow. Wait! What time did the clock just strike? Oh, my heavens, I've been awake for an hour. Okay, relax. Take deep breaths. Do that tighten and then release the muscles from the toes up thing. Oh, gosh, now I've got a leg cramp. Darn! Is it getting light outside? Maybe I'd be better off if I just get up. But I've got a couple of hours left to sleep. Okay. Try again............ Remember to call first thing in the morning. Oh, yes. Tell You-Know-Who about the drawer that's broken. Should I just go on and get rid of those clothes that don't fit? Am I ever going to lose weight? Maybe I should join the Club and go to some of those exercise classes for overweight, old people. Are you going to call tomorrow? Probably not. Why not? It will be good for you. You're never too old to get in shape...at least some kind of shape. Okay, that's a good idea. Well, maybe if........