Hey this game is a lot of fun! I like the combo system, it feels great to hit 3 or 4 enemies and hear the sound effect get higher in pitch. Thanks for the shoutout too!
My main complaint is that the levels don't really feel like they are laid out with the core mechanic in mind. I was hoping to combo through the whole level, but it doesn't seem like it's possible with how the enemies are spaced out. There are several jumps that are just far enough apart that when you bounce off of one enemy and try to plow through another, the combo timer runs out right before you hit them and you end up taking damage. Here's an example of what I'm talking about https://gfycat.com/TightAdmirableLeopardseal
Maybe the combo timer should only run down when you are touching the ground?
You did a good job on level design in the time frame given, I know in a game jam there isn't a lot of time to rigorously test levels.