Really fun concept and it gets really chaotic when it starts shooting a whole bunch of balls at a time. It also has a nice aesthetic.

The game feels very solid and the art although simple, fits very well. I didn't have someone to play with so I didn't get the full experience but it looks like a fun concept. 

I thought the screen shake was a bit annoying once there were more than 5 balls on the screen. Maybe you should consider having an upper bound for the number of screen shakes permitted per second.

Great job!