He was fine last night, and there is nothing in our house that he could have cut it on? Do paw pads split on their own. This split is all the way across and a 1/4 inch deep, but no blood. He woke up with it this morning and can't walk on the hardwood floors or the sidewalk. He is ok on carpet and grass, but moves very slow. Should I get stitches for him or will it heal on it's own?