Well I found out my story is not going to have a happy ending. I suspected it from the beginning but now I am really pretty sure it's going to end badly, especially for the main character.
After writing the last couple of 'chapters' I'm pretty sure I will finish as well, maybe with some words to spare. I wasn't sure but I managed to write maybe 7500 words in a couple of chapters and events so I'm pretty happy with that, and think that as long as the big conclusion takes the 10000 words I'm expecting I'll be fine. If it doesn't I can always plot-twist the **** out of it and bring in the time lords.