This is really cool! Good job! I had fun playing it, and I think that if you come back to the idea later with more free time on your hand, you definitely could expand it and make it into a whole story.
I like the idea of the player roaming through the other ones, but then become stuck in a box and seeing themself walk by doing the same thing they did earler, going to the exit.
Definitely better than my platformer. Good job!