A few things could help to improve the game, as there's potential.
1) Explaining control scheme on the page or within the game itself - I wasn't sure what to do with the main menu at first.
2) The music seems to play in the 1st level but not the others + dying results in the music restarting on top of the last bit of music playing. At one point I had 4-5 tracks playing simultaneously
3) It looks like you can't jump while holding a direction key, I think that might make the game tad too hard
4) Few times where I landed on the moving platforms only to die instantly cause it moved away without me
5) Perhaps add a screenshot of one of your levels on the page too !! Show people what the game is about ;)