This game is quite good for only 2 days of work! Assets look nice, functions well, etc.
If you do plan on continuing work after the jam, a couple notes I have: It would be nice to have a better indicator that you are being damaged, something as simple as your character flashing would help. Also I noticed if you let the enemies pile on top of you near the beginning, they won't be able to harm you more than once. More specifics on upgrade details and other UI fixes would also be cool.
Other than that, good job and good luck!