The screen movements are very jittery and that make watching and planning movements more difficult than it should be. Try to smooth it out. Also, he seems slide around more, like when landing on platforms, and thus, he keeps moving right off the platform and falls into spikes. The hitbox on the spikes it very large. Since he can't have his head go thru platforms, making the climb at the end of level 2 was annoying. The music is ok, so keep that. The controls, however; if you use arrows for left and right, why use other keys for up and down? Use up and down arrows for up and down. Don't ever use Shift or Ctrl, as they're system keys.
Keep at it. When it's fun for you to play, it might be fun for us to play. Never submit something just because it works, but wait til it's fun; which is the point of games. :)