Good start...
First of all, its a good concept. I also enjoy simple characters for games (as you can see by the game I have made) and the sloppy style. Rough drawings are far more creative than generic shapes in my opinion.
Anyways, you say you put so much work into making your levels, so make it so you can't right click the stage and click 'Play' to skip the current level.
You can do that by easily putting the script "Stage.showMenu=false" into a frame.
Also, I'd suggest adding some kind of health meter so its more challenging.
And while playing, I noticed the first boss walks off screen, causing you to fall and die.
Just play around with it a little more, I'm sure it'll turn out pretty good in the end.
Goodluck.