Aim for an intentionally crappy first draft and take the pressure off!
You are certainly in good company -- I wonder why so many of us put off that last class/thesis/whatever before graduation? I waited two years to take a test required for my last degree. The amount of time I spent dreading it and beating myself up for not doing it took way longer than the test or studying for the test. My brother has had 'one more class' for the past few years. It's very common!
Good luck with the camp nanowrimo! I hope it goes well