Arg!! Me too! I'm full of all sorts of academic doubt, paper finishing terror, and longing to get "moving" again--whatever that means. (I've been very fidget-y but that might just be the sit in front of the computer 10hrs/day freak out about writing 100 pages talking.)
There a change in the status of your dating availability dB that I don't know about?
But more importantly, just remember you'll eventually push off those fantasies. As was said in High Fidelity (a new comedy of remarriage, now that I think about it-I'll add it to the very short list that includes Say Anything and Eternal Sunshine) the fantasy is just that; it isn't real and it doesn't ever deliver.
Also I find that late night exercise helps. I haven't done it in a while since I currently live in a neighborhood that I don't feel comfortable in. But put on your running shoes and run around the block, or better yet ride around the block--by the time you get your bicycle out of your apartment I bet you'll be wanting to get into bed. Good luck!