Cute game. Since you're looking for feedback:
During the first level, I got confused what the game wanted from me. I think it might have been better if there was more feedback when breaking the walls; audio, particle effects, screen shake, etc. Game Juice. Or even break them in one go.
The second thing is challenge. Simply pressing a button and then being allowed through is not that engaging. Maybe you have to earn a new shape, or you can only change between a set of X shapes and need to move back and forth through a level in the correct order. Especially for a game jam, people have very short attention spans, so you need to be wary not to bore them in the early levels, even if the later levels are awesome.
Regardless though, well done! Especially for a solo dev. Making something and putting it out there is what's most important, regardless of how bare bones that thing is!