The idea here is awesome! Great job making this in 3 hours!
If I may give a couple points of more critical feedback, I agree with ProSmashy that the orange foe teleports a little too often. Additionally, I had several instances where the ball passed just slightly outside the hitbox for the portal. It might even be fun to add a mechanic where the ball's path is affected by the nearby portal trying to suck it in. I also had a hard time keeping track of the white ball falling amid the other white orbs falling at a similar speed in the background. I'm not sure if it's intentionally meant to be distracting or not, but it was frustrating.
I totally understand the pressures of the game jam and that not everything you want in the game can be there, or get enough polish. I really hope you continue to develop this idea because it's seriously cool!