This is a fun game! I didn't understand what was happening when the circle turned blue at first, but SpaceQuackers' comment cleared that up for me and then I had a great time! I sucked though, with my high score at only ~2200.
The ball growing larger as you play was a nice touch that helps with the out of control feeling. The mouse control mode felt much much easier than the bullet hell dodging mode too.
Great work!