I see this is your first submission, and inself it is not bad. At least it have the basis of jumping on platforms and no game breaking bugs were found in my runs. But "not bad" do not mean "good" either, as the game have some flaws.
1st one, I suppose that the ennemies ARE supposed to kill you even when you jump on them. (if not, well, there's a glitch since i died every single time) . It could be a good twist, but unless specified in the description players suppose they can defeat ennemies by jumping on them, so this may lead to many deaths.
2nd, the game over method, as the game is really unforgiving. Miss a jump, back to title screen. hit bad one single ennemy, back to square one. Not even 3 lifes to restart the room, nothing. At this point, the game's lifespan rely much more on false dificulty than on skill and actual lenght.
I also seen a minor bug, when walking to the left the animation works, but not to the right. It stay on idle pose. Nothing game breaking, but don't forget to polish your game's animations.
For a 1st try, it is not bad, keep up training ^^