You mentioned that completing the work that's still left has taken you about 23 days (for the history of japan video). Then, you say that this video is about twice as long. That means, that with the new deadline of Dec. 15, you will have to do about 46 days of work in 25 days! Your dedication to your deadlines is inspirational, but how do you reconcile the fact that you've already pushed back your initial deadline, yet still have to work at almost double-speed for another month to finish this long project?
the same way you reconcile escaping from a burning building