My dissertation (a philosophy dissertation) is due in on the upcoming Tuesday (so, the 29th). And I'm yet to start writing it. And the bunch of events leading up to this have left me writing about a philosophical problem that bores me, addressing some of its important facets via approaches that bore me. And here I am looking at TSR. :-p It hasn't ended up like this (solely) due to laziness on my part - there are reasons for it that I won't go into. But I sure am envious of your 2,000 "words of substance"!
I can't offer much in terms of advice - but under the assumption that you've done OK until now, I don't think you need any. As insincere and easy as it sounds, I'm sure you'll end up fine. Given the volume of the dissertation, it obviously gets far more intimidating as the deadline draws than, say, assessed essays, but that's just it - intimidating. The next week is going to be a pretty ****ty one but you'll get those words out somehow. A housemate of mine wrote the entire thing over a weekend + an all-nighter, for example. You might want to consider doing one before the deadline too. I'll leave you with this:
"To achieve great things, two things are needed; a plan, and not quite enough time"
-Leonard Bernstein
Now get off TSR and write.