If you ever feel like you should stop to think, ignore it and ramble your way through the tricky portion. Good things can come out of writing on the edge of your seat like that. At the very least, more words to get to your goal. And good luck!
If you feel like you're at a pass, unable to think clearly or maybe your character is backed into a figurative wall and you don't know where the story is going.... word vomit --- or write and excerpt for where you KNOW you want the story to end up and if there's time/you need more words, You should be able to figure out how to get your character to that excerpt point after you've written it out. GOOD LUCK!
Unfortunately I don't have anyone to challenge except myself.
I think I'll be running on a latte tomorrow to make sure that I can power through my final four thousand words. Keep up the words of encouragement smile They really mean a lot to a writer.