Nice retro vibe, a nice clever take on side scroller with the bubble mechanic, it holds up quite well, lots of little mini-puzzles to resolve. I love the pallet, you tried to capture game boy with it and you most certainly did. Sadly the same thing that annoys me about the Gameboy annoyed me here... Sound and repetitive music. It was really off, it went from cute to irritating in about 2 minutes.
But other than that, great entry, really impressive how much you got done here in 5 days.