I love games like this when they're programmed properly, and this one is.
The physics and collision detection are spot on (well maybe the hitboxes on the enemies could be a tiny bit smaller but yeah).
Also I liked that you used a higher resolution than most other flixel games, makes it look a lot prettier.
The medals were a bit too easy, but maybe I just think so because I wanted an excuse to play this game longer. Maybe could have increased the number of levels a bit?