I really like how you pulled off the cel shading with the palette. It works really nicely! The game itself is also very fun, with great music and excellent level design. I can't believe you got so much done in such a short time!
My only criticism is very minor, I couldn't find a way to flip the vertical axis for movement. I couldn't rewire my brain to press 'W' to go up, and kept on trying to "pull back" with 'S'.