I really enjoyed this game. Those spike tunnels are such a challenge!!! I really had to BE the leaf... no room for panic. It totally reminded me of that Firefly/Serenity reference, "I am a leaf on the wind". Unfortunately for me, I'm not a very good leaf.
The music is such a contrast to the floaty, graceful leaf and I felt like it was antagonizing me, letting me know how futile the effort was. If you were going for melodic chaos, you nailed it. Honestly, it amps up the angst, so when you have so much floaty, open space, maybe that's not a bad thing if you're trying to create tension for the player.
The art style was simple, but it accomplished the goal. I'd recommend setting up your colliding mechanism (or whatever triggers a hit) closer to the actual spike image. I felt like level 4? with the big spike tunnel was causing a collision when I was about 1 pixel away from the spikes. It led to a lot of frustration and frantically smashing arrow keys. I'd also recommend making sure the baddies contrast with the background in future games. I didn't realize that the spikey balls had spikes at first. Going with the theme, it may also have been cool to switch up the look of obstacles so that they related more to the plight of a leaf... like drops of water instead of spikey balls.
My favorite part was the text in the pit and the "hidden" reference to zelda in your first level. I'm a huge fan of hidden areas.
Great work on this. Hope you had fun making it!