Thank you so much for your feedback!
This is our first jam of this kind.
Yes, I agree, the 10-minute timer is too long. We initially wanted to set it to 5 minutes, but after a couple of tests, we were afraid most players wouldn't be able to keep up (we wanted to simplify it, since it's a jam).
And we do have a bad ending, and the timer was supposed to trigger it, and it even worked, but we didn't have time to test it. In the end, I only noticed it wasn't enabled after the submission xD. That's the reality of Game Jam.