Nice work! It's very cohesive, especially for a game jam. I do have a few notes, though.
You respawn far too slowly. Moving around in a bubble is fine and all, but I got very sick of it very quickly. Especially in the level where you're supposed to jump into a pit and onto the target (with the "Hold Jump to go farther" text) It was incredibly aggravating to miss the tight jump and have to wait so long between attempts.
Other than that, it's a very interesting concept you could easily turn into a full game, with some extra polish. Very good work!