Fun game! The concept is superb, and the boss at the end was quite the formidable foe! I appreciated the level design, and how there was flexibility in the number of coins needed to clear some levels, and how there were multiple ways to clear others. That said, I did find aiming the cursor while platforming to be a fairly difficult task, but fortunately not too many levels required both to be done at the same time.
I did encounter some bugs. Running into a wall and jumping at the same time will cause the character's jump to be heavily nerfed, so it won't be able to jump onto whatever platform it was planning to, which is frustrating. (Especially on that rising lava level! I definitely missed having coyote time for that level, too, although that's a game design choice rather than a bug.) But more curiously, I encountered a bug where I could generate infinite coins by shooting coins downward near the top corner of a room - the end result of which can be found in this screenshot:
Overall, you have an extremely polished game that is one of the few from this jam that is pretty much a finished product already. It'd be amazing enough that you made this within three days for the jam, but I see you submitted with over a day left, so you really did this in just two days! You should definitely be proud of what you made!