Good concept - would like to see it expanded on. The player and enemy sprites look nice and the controls feel very responsive.
I would've liked some more feedback from the game, when I hit enemies or myself with the shots - maybe a sound, some particles or tiny amount of screen-shake. I could see this becoming a nice hack and slash game :)
Good effort.
If you have the time, I would appreciate it, if you checked out the game that I made for the jam :3