I like the stylish presentation a lot! HOWEVER. ;) I have the same problem as what EpicBoy described above; the game slows down very much when the circle effect is happening. My guess would be that there are simply too much particles being created and moving away at that moment. It is especially bad when the ball gets stuck behind a pad, which sometimes happens; it collides continuously and thus an enormous amount of dots is created! Maybe make the dots smaller, reduce their amount, and make them disappear after a very short while. The effect will be less spectacular but it will not slow the game down as much. Or maybe, if you didn't have this problem on your own computer, include an option to switch the effect off or to turn it down a little bit.
Good work completing a game!
Good work completing a game!