My hands are quite burned, not self inflicted though.
(Me and my mates made a fire, someone chucked a deodorant canister on, blew up, some plastic smoldered on my hand as a result of the explosion.) It wasn't painful at first, but when it's healing, that's when the pain kicks in.
They skin tone is just slightly different.
(If you want to harm yourself, do this.) Atleast you won't die. (ON A SERIOUS NOTE I WOULDNT RECOMMEND SELF HARM ANYWAY. TALKING TO SOMEONE IS THE WAY TO GO.)