A simple, and competently made game featuring a resource system. The two of you did alright for your first jam.
One quick tip, though. I had a problem where my mouse could escape the window and click off the game. The rapid clicking nature of the gameplay loop makes this a bit of a problem. You can solve this by using "Input.mouse_mode = MOUSE_MODE.CAPTURED". This should stop the mouse from exiting the window during gameplay.
Overall though, congratulations on a competent submission. Raise your ambitions and come back in January!