My biggest complaint is that the death animation is REALLY slow which is frustrating especially coupled with the difficulty. I keep dying and every time I die I have to wait upwards of 5 seconds before I can respawn. It really was to the point where it felt border line unplayable, if you release another version with real fast respawn I'd be on that shit like butter. Also, I don't like that you can recall your bullet because it feels just like an extended reloading animation rather than an interesting mechanic. IMO I feel it should just be you have to retrieve the bullet. However the idea itself is good. The level design is nifty as it allows for slight chaos without feeling overwhelming. Everything color wise is also very clear. I recognize what bullets and enemies are and can gauge what they do easily as well. I also like the death animations both for the player and the enemies. The particles are nice and the splatters are real satisfying.
Good work!