I liked this idea behind this game. The 'switch' mechanic is pretty neat!
For feedback: I think some background music and sound effects would really help bring the game to life. Probably surprising to hear, but the first level is actually tough to execute until you know what you're doing. I did spend a lot of time trying to use 'E' to grab AND throw per your instructions. But while holding them, 'E' just sat them down and then they laser eyed me. Right click (per instructions) doesn't appear to shoot either. What did work is 'E' to grab, mouse to aim, Left click to throw. I think it would be good to have an in-game prompt to press 'Tab' to introduce players to this main mechanic. Death comes quickly in this game.
I really do think that you have a cool mechanic and the start to a potentially great game.