As short as it was, I was very pleased figuring out what to do and what the controls were. The movement change once you obtain your mech is oddly satisfying despite how it's a downgrade in terms of speed. It captures the sudden bulkiness when you finally get it and it's a nice confirmation that yay you got the thing. Realizing it was also a spring was fun to figure out. I ran into one bug where if you fall down super fast, you get stuck in the floor and can't move horizontally. Jumping out of the ground though fixed it, so it's not a frustrating collision bug.
Visuals remind me of older games like on the Atari, so I wouldn't mind seeing you explore that further with changing the environment or using different color pallets for areas. Maybe an option for a CRTV shader?
Good progress!