I accidently stepped on my dogs front left paw about a week and 1/2 ago......He was favoring it for a few days and seemed fine after that......now he is limping and holds it out to the left when he sits instead of straight ahead,,,,,I have checked his paw and he doesn't seem in any pain when i squeeze his paw or leg..........but he holds it up instead of letting it rest on the floor....I don't know what to do....he is 9 years old and part German Shepard and Husky mix.....Please help.....