Da Pink Knight Frustrating.
Here's the deal: Games can be frustrating and still be good. This is achieved by giving the player a sense of progress. The inclusion of character leveling is an easy and proven method of doing this. When playing your game, it felt good to know that I was unlocking more powers as I succeeded.
But here's where you failed: you went and included leveling down! Sweet, I'm think, now I can double jump and dodge that God-forsaken saw attack. "JK!" says your game, "Level down attack! Now you can't!" All of a sudden, there's no sense of accomplishment to leveling up, because it'll just be taken right back. That's incredibly frustrating. It's no coincidence that hardly any successful commercial game doesn't include leveling down: It's NOT FUN.
There was one other big problem, too. Generally, it's a bad idea to let the enemy hit you while you're down. Again, it's just frustrating. You could have solved this problem by including a more potent recovery move. Maybe tap up or down to roll back into a fighting stance, or press shield just as you hit the ground to keep your footing.
I realize most of my review seems full of vitriol, but it's worth pointing out that those really were deal-breakers, and that the game in general is quite good. The art design is great, the story is humorous, the basic physics and controls are intuitive... there's so much this does right. I really wish the gameplay wasn't so frustrating.