Really cool entry, I love the music! The art is really good too, although the orange piping in the background is a little busy.
I have two pieces of feedback. The first is that it feels very strange that falling after a jump is floaty and controllable, but if you just walk off a ledge you fall like a ROCK. Just straight plummeting.
The other main thing is that the level design definitely needs some work. In the sixth stage, there's an entire section of platforms to the right that if you touch, you just have to kill yourself on the spikes to start over. You just need to fall into an earlier hole and hit the teleporter, which you can't really know until you've gone too far. The level design issues were most egregious in the final level, where you can't see the spikes below you, so it's just a trial and error of dying until you find the correct path, and that's really frustrating for the player.
Overall though, a really great entry, and I had a lot of fun! Great work!