some things you should consider
its not bad, but somethings annyoed me. for starters the enemies looked like a cross between a banana peel and a ghost, you didnt reset the Y position when a leaf was collected...thats not a hard thing to do, even if this is your first flash. the music got annoying quickly with no way to turn it off. the background images were nice. you could of also had a diffiiculty setting, for example easy would have a few lives before you got game over. hard mode would be like the game above.
on a positive note, i did like the little arcade noise when you failed, reminds me of happy times when i was a kid lol.