I was petting Lucas near his back end and he yelped really loud, put his ears, back and jumped. It's his left knee....I felt that area again and again he yelped He's been limping a little more on that side and I just noticed when he stands still he leans all his weight in the back on his right side I mean he is putting almost NO weight on that leg when standing still! When walking he kinda hops so there isn't much weight on it I gave him an aspirin and am gonna have to see if the vet's open tomorrow. I was thinking x-ray his knee to see what's going on.....what do you guy's think? I'm sure the vet will say what they think. I just wonder what's wrong. I don't think it's the arthritis, especially since it's been bothering him a while. I hope it's nothing too bad!