What the Hell am I thinking?

I've finally done it. I have lost my mind. Last night, I signed up for NaNoWriMo. As if there wasn't enough on my plate. In case you're wondering, here's what is on my plate:
1. Three kids; ages 3, 4 and 10. The three and four year-olds stay at home with me during the week while ...
2. I work nightshift, three 12-hour shifts per week [in which very little writing can be done] and sleep the day after while...
3. My husband is back in school full time to become a Respiratory Therapist. He's gone all day Monday, Wednesday, and Friday. On either Tuesday or Thursday, he goes back to school to study with his classmates. Every minute he's home, he is studying. This is paying off as evidenced by his A-average.
4. I'm editing my first novel and really trying to take a more business-like approach after SiWC. Last year I pitched to an agent who requested the first 35 pages and this year I pitched to an editor who wants to see it (upon its completion). I learned that NaNo is not the right way to do your rewrites. I tried this last year and got 50,000 words, but it was all backstory. NaNo could very well pull me away from the Book That Needs Attention.
5. My house is a disaster zone.
6. We're traveling Nov. 23-27 for Thanksgiving

So!  I figure I've got around 20-25 days that I can actually write, which puts my daily word count goal at 2,000-2,500. On the plus side, I am kid-free for four days this week. I'm aiming for much higher word counts on those four days to make a buffer for the aforementioned holiday travel.

Plan: Write out the list of scenes I need to finish the first book. I've spent the last few months ripping the SFD (shitty first draft) to pieces and I have many holes to fill. Start the next book. Ideas for this have been bouncing around like so many ping-pong balls in my head for the last year. Lastly, Try not to kill anyone from the stress.

Somebody tell me this is actually possible. Please.