Hey! Some feedback:
The idea is really cool. There was a cool moment for me when I was in the first big room, the one that introduces the 'low energy' physics, where I was really carefully paying attention to what physics mode was on, and getting ready to react to the best one for the right situation, and it was really fun to engage with the game like that! Could totally see a Super Meat Boy esque hard puzzle platformer out of this as a full game, with maybe different worlds and levels having different sets of physics modes they swapped between.
My issues with the game were mostly that the controls didn't have a lot of feedback to them which made it feel imprecise to control my character. So the character starting and stopping max speed on a dime but not automatically slowing down in the air when you let go of both keys made it really hard for me to platform properly.
Oh, and there doesn't seem to be anything making sure that modes can't swap back into themselves a set number of times. Sometimes I was just sitting waiting for Low Energy mode to go away for ages before I could finally make a jump I was trying for!