This game is extremely difficult and repetitive. I don't mean to sound harsh (or you know, like a dick) but the game requires extreme precision with very little room for error. The controls feel a bit delayed, and the lack of sound effects or music makes it boring. I can't critique the graphics; it's good for what it is: pixels and a pix-elated world but it seems depressing at times.
I also made it to a part where it was almost impossible: how does one duck and jump at the same time and avoid both obstacles?
If you can fix it up and make it more appealing, then it'd be a good game.