From one pixel artist to another: Your art was fantastic. Very cute, nice and chunky but also well detailed.
Attacking and moving were very slow and a bit awkward. Also, the splash damage on the fire attack was very large and I frequently died wondering what happened. Honestly in a game like this, I think it was unnecessary (unless you are going for realism or there is a balancing reason for the mechanic, making one of your normal attacks punish you for using it can hinder the experience.)
I'd reuse this art and up the tempo of the game play. Make the jump a bit heavier and allow attacking to be more frequent and safer.