This is the player character from Plasma Fist, one of my freeware games(originally released in 2015). The player & tiles are all 10 by 10 sprites.
Hey, this is VERY COOL - I love how obvious it is that little pixel dude is falling down. I'm not sure you can make this sprite any smaller and keep it this clean - grats!
Ok I added a link to the unscaled version in the description.
I know it is already pretty tiny, but can you please upload an unscaled version?
in-game he actually stays knocked down a second or so and there's a lot of screenshake.
Ha! Love the way the force of it blows him back and he just gets straight back up and starts running again. That's a plucky 100 pixels.