Awesome job on your game! You have a good amount of content for such a little time frame. I am so glad to see so many different enemies! You also had good instructions on how to play, sound effects, musics, and hand drawn characters.
Both me and the wife were talking about the Boss's attacking death sphere. I am really impressed by that mechanic! I am sure that one was fun to code!
I'd say the next step for you is to polish up the art a little, give me a back story, and start pumping out those levels so each of those bosses has their own domain.
GREATTTT JOB, DUDE!