Has been happening to me too lately…
I think it’s because there is something going on in your life and you either can’t really realize what it is or you don’t know how to solve these problems, so you tend to think a lot. At least that’s what I think is happening to me.
Keep a healthy lifestyle and exercise, don’t oversleep or spend too much time in front of the T.V. or laptop.
Let go of your mind, practice some yoga if you’d like to.
Lock yourself in your room, get your iPod, put the volume to the maximum and start dancing all of a sudden :D
It will somehow restore your energy, so you can do anything that you like and increases your heart beat rate – you’ll suddenly feel happy and relaxed – I know it works for me.
As of the procrastinating problem, it happens to me to, I’ve been behind a lot, most of the times because I do random stuff that I don’t necessarily find fun, I’d go on yahoo answers for example, and answer to all these crazy questions but I don’t really have any point of doing so… XD
Anyways, just try to keep your mind focused, and promise to yourself for example that you won’t go on YouTube after you finish your project! If you don’t respect that promise, then punish yourself. I found this method by myself and practice it sometimes… I don’t know if others do this, but I find this somewhat effective :)
I hope this helps, I’ll also go ahead and actually try to do what I just suggested you. Good luck!
(If you want to, consult a psychologist, I just gave examples/suggestions according to my personal experience, (:)
my personal opinions and ideas