First things first: your art is looking really good! Also the music plays nicely together with the games speed, and the sound FX are well chosen.
Unfortunately I am really bad in playing such games. They let me feel like I have the reaction and motor skills of a rusty bathtub :-D That's why I haven't much to say on this side. I tried my best, but my doges were way off and so were my atttempts to hit the boss. But I assume for the right player this is a fun game to play.