Cool concept! The recoil of the main projectile made it really fun to zoom around. I didn't use the coin much because it was a bit slow to successfully use, but that's fine, just my playstyle. Some more enemy types could certainly have helped spruce things up here and there!
I think the biggest flaw is the lack of checkpoints. Though since it's a quite short game, that's alright and it actually forced me to learn the level layouts and speed through them, so maybe it helped out in the end!
Good job on your (from what I can see) first jam game!!