Will also add my voice to the people saying there are too few levels and the levels are easy. I'll also say that it's missing some UMPH!
I think moving should feel more satisfying, maybe a ramp up in the speed, a screen shake when the ball hits a wall, squash the ball when it's moving so that it feels faster, particle effects when it hits the wall. You did add in sound on hit, which is a great start and already adds a lot.
Of course these are all polish and if you didn't have time during the jam, it's OK. They're still super important though, even for a game jam game
Just something to keep in mind 👍