The controls are a bit akward. Especially jumping, I think it has something to do with your collision detection which is questionable to. I made it to level 2, fell down and nothing is happening. There is only one level finished? Anyway, a good platformer takes a lot of time and dedication, you should not aim for making such a game if you haven't got the time or skill. Try something simpler first before reattempting something like this.