Very cool!
I liked the second mode with powers up that the ball can collide with and can change your paddle. That kind of variety helped the gameplay. I also liked the overall look of the game; the trail on the ball was satisfying. I did find that the mouse sensitivity was a bit too high; i couldn't control it as well as i would have liked. Also I think it would be helpful if the player had the choice of when to start the round maybe with a press of a button. There were times late into a match, when the ball is moving very quickly, where the round started as i was trying to get my paddle back to center and it had already scored on me by the time I got back.
Great job though!