Wow I'm starting to find more and more very good game from the game jam submissions and this one is excellent and professional. Graphics are simple but very polished. The controls of the character are perfect and smooth, this choice of a high gravity is properly used by the level design. I really enjoyed your game, even if sometimes, I was a bit frustrated because I had to restart the room below when I felt.
Oh and I died once on a corner of a platform (with blank spikes) but that was the only bug I had.
Really good job !