But that's part of the fun. This happened to me last year, too. And when I do NaNo next year, chances are it'll be another repeat of years past. I think, for me, anyways, that the decompression is a very necessary element. By the time November comes to a close, I'm so tired of the writing marathon that I know I run the risk of true and complete burn out, the type where I never want to see the story again. And that would be bad.
Today is the first day that I even looked at my manuscript. It was mostly to get some feedback on a big edit I want to do, but I still looked at it. I think that I've managed to catch up on all my sleep and my head is starting to fill back up. Which is handy because I have about another fifty thousand words until the thing is complete. :)