Cool game
Regarding the music, I’d suggest using shorter notes for the melody; the raw sawtooth wave is harsh on the ears. You could also add some vibrato to make it less hursh.
Also, for some reason, the controls didn't match the game's description at all (I spent about 10 minutes trying to figure out the inputs—it turned out to be Left Alt, Left Ctrl, and the arrow keys).
Otherwise, the game is actually quite interesting. Great job!