You have some very good things going for you in this game. The running jump was done nicely and I like the style. However the gameplay is rather boring. Perhaps find a way to spice it up? Maybe not take such small steps in introducing the player to new gameplay elements. idk, I'm sure you can come up with something better than I could ever think up. :P
Has issues, just a few.
First off, the graphics are very well done in a sort of retro pixel-y style accurately befitting the title. I was fairly impressed with the parallax scrolling, however it seems like that would better fit a set of larger (wider?) levels. The jumping mechanic seems to be pretty decent, although after dying on the third level, my character was still able to move for a few seconds, despite being a dead blob.
The sounds, however are nothing to write home about. They don't really seem to sync up quite right with any of the action. Not to mention, the music sounds like something from the bad-old-days of cheap and dirty MIDI soundtracks, complete with what sounds like a bassline playing where there should be drums.
Overall, not a great first outing, but plenty of room for improvement.