it's not bad, but i would get rid of the mouse shot and manage all with a joystick or keyboard.
It has a bug in the restart button, don't fully refill the ammo(feel like replentish random amounts) but somethings i have to restart 2 or 3 times because don't refill the hp bar.
A tip for the pixel art idle animation, the feets shouldn't look both to the same direction, it feel unantural unless are a walking frame , as is holding a weapon the back foot should be pointing to camera. And other thing that hel the animations, its not made on the black move the reflextion the bright color should acompany it, if not it apear its deforming instead of moving
https://lides.itch.io/npc-buff-pack(this is a asset packs I made you can use as reference, has the animations bones, and a characther "the general" were it's more clear the thing i said)