Nice concept. I wasn't able to get past the shooting enemies on level 3 (they shoot through walls, seems a bit unfair). I think that it would have been a lot easier with a touchscreen, or if you didn't have to click on the ball to start a new swing. If it's that fast paced, why not let me click and drag anywhere on the screen?
The music was nice, and the sound effects were good, though you could definitely add more.