Hey, it happens to the best of us! Even though it's incomplete now, hopefully you can find some time to finish it up after the game jam :) Out of curiosity, which engine did you switch from and to, and how come? Did you feel like you wanted to learn something different?
Hopefully you got to learn some things, maybe even around time management. It's a very difficult skill to prioritise what needs to be done, make sure you don't have much scope creep, and you're focusing on the highest priority things and cutting everything else. I hope your next jam goes more to your plan :)