Now that Nanowrimo is done for another year, how do you feel?
Are you upset because you didn't make 50,000 words?
Are you upset because you feel that you've written crap?
What do you do with yourself now that the frenzy is over?
What do you do with what you've written?
Well, firstly, if you didn't make the 50,000 word limit, don't beat yourself up. In the 5 years (I think it was 5) that I participated in Nano, I completed it once. Do I care? Nope. Not really. My life is busy. I have a job, kids, a household to care for, and other writing clients...it's a juggle.
Secondly, if you feel you've written crap...well, ya, you probably have. You just clumped together 50,000 words in a short period of time, there's a good chance that it won't be a cohesive story at this point. That's why you have to edit, proofread, etc, etc. You've laid the foundation, now you have to build on it.
Thirdly, do not bother beating yourself up about not doing it all in 30 days... it's not worth it. What you do next with your writing is what's important.
What will you do next? Maybe take a break from that project to refresh your mind. Maybe start a different project. Then, a month later, come back to your Nano story and start re-working it.
The main thing is to keep moving forward.