Exactly! But don't worry, I wasn't so efficient in my first game jam either... had to cut out a lot, and barely finished a decent, fair, working version in time. After you get a couple of projects done, you will be able to more accurately predict the amount of time each feature will require to implement, and even then, you need to leave 10-20% of the entire time-frame for a last phase debug session, where you share your game with 10-20 of your trusted gamer friends, and fix as many bugs as you all can find.
This fox game is promising! Hope you make fun games in the future! Cheers!