As a scientist, I know a little something about momentum.
Believe me, I know how you feel.
But hear me out: Take a break.
Walk away from that manuscript for at least a week. You need a little perspective on your work - a little distance from it - before you can launch a successful revision.
That's how it was with my friend as she was working on her first YA novel. The sequel is coming out soon, but she struggled with the first one enough to give up on it at least twice, to put it away and decide it was just a failed experiment and to chalk it up to experience. The funny thing was, though, each time she walked away from it and began working on something else, she found that she'd gained enough perspective on the manuscript to really see it, to recognize what worked and didn't and, more importantly, to recognize how to improve it. She'd gotten the necessary distance and perspective by taking a break from it.
I'm not suggesting you take a huge break and come back next November. But I would advise taking a week or two before you jump back in to your manuscript..
Life after NaNoWriMo can be a bit like life after battling aliens. After the team and I fought the Chitauri, we were exhausted, relieved, and a little shellshocked. I just wanted to move on to the next big battle and get that one over with, too. So when Tony suggested we all meet up at a diner and eat some shawarma, I thought, as I often do, that this guy was two bricks short of a truckload.
But he turned out to be right for once. And not just because as you can see, this diner made really good french fries. It turned out that we all needed a break, a change in focus and perspective. (As you can also see, even a god like Thor needs a little time off from saving the world. And that guy can put away some food. He makes Hulk seem like a sparrow in comparison, appetite-wise.)
So take a little time away from your NaNoWriMo manuscript and let it percolate in the back corner of your brain for a little while.
Stop and smell the shawarma and come back to that project refreshed and ready to revise. And then unleash it on the world.