After one month, I've written 27,000 words of my novel. I have another nine chapters to write, though the story keeps growing longer than the outline I mapped out. My current pace of 794 words a day would reach 100,000 in 125 days.
If I were to end the book abruptly -- "and then the meteor struck and they all lived happily ever after in the tragically few hours left to them." -- I would have completed a novella, which by convention ranges in length from 17,500 to 40,000 words. So at a minimum, I can now call myself a novellaist.
If I had stopped the book between 7,500 and 17,500 words, I would have written a novelette and could thus be described as a novelettist. This title is far cooler because it sounds like librettist, a person who writes librettos.
When I started I was obsessed with word count, because I wasn't sure I could carry a story over enough words to constitute an entire novel. My impression from limited research is that a thriller should be at least 60,000 words and no more than 100,000 if you're a first-time author.
As time passes, I'm focusing less on the word count and just trying to tell the story I plotted out in full.
Writing a novel for the first time has been entertaining, though it's already making me a weirder person. Two weeks ago, I went out to eat with some relatives right after finishing a particularly distraught scene in the book involving two of the main characters. I was poor company during the meal because I'd become distraught as well. I was so attached to the characters that I didn't want anything bad to happen to them.
I got over that pretty fast. Now I'm as merciless with my fictitious creations as a kid with anger issues playing The Sims.