Cute retro game.
Beautiful pixel art, but pay attention to contrast: the enemy's color (only the mouse) are too much similar with scenario, which makes it a bit complicated to see sometimes. Change the mouse's color to purple (from palette) with a white outline should work.
The gameplay really catch that older games feeling, maybe a little too much: The wall sticking movement need some polish. Maybe make it automatic when pressing the move key in the direction of the wall would be a better configuration. (Canceling pressing 'down' or 's' )
Overall it was a good platform. Congrats!