Well done! Nice little sprites! That art looks really nice for just 48 hours!
I like the core idea here - especially the part about ammo and power being inversely linked. That's a nice touch. However, it just felt a little too difficult. I think having some sort of knockback OR enemies having less health would help it feel a lot better to play. Right now, it's too easy to get swarmed and trapped with the knife and end up taking a bunch of hits before making meaningful progress.
The weapons felt cool to use. I really liked rolling the laser.
Congrats on your game and keep making stuff!