Plot arc?

I'm scared. Do I have a plot that will stretch all the way to 50K? Or will it sputter out somewhere in the mid-30s, only to leave me prostrate and shy of the mark?

So far, I've just been winging it, trusting my memory and instincts and characters to guide the plot forward. But today I actually sat and detailed some of the possible actions that could be included. The NaNoWriMo folks talk about having a story arc pretty clear at this point. I'm concerned that my "arc" is but a plane, flat and dull, like documentary footage without dramatic impulse. Perhaps some of you experimental film buffs might enjoy that, but I'm hoping to entertain here. Writing with no clear plot arc feels kind of like walking a tightrope: exhilarating, but not exactly pleasant.

Oh, and I employed another tool today: the Onerosity Coupon. I pledged to hit 35K by Friday or I would have to undertake a particularly onerous task for a friend. So if you have some heinous task you need doing, by all means track down your NaNoWriMo friends. Either you'll get credit for being a super-supportive pal or you'll get your stuff done. Win-Win, atleast for you.