I have a 6 month old male who is a giant goofball and also very excited when we are playing ball. I would guess he is 65 lbs? He has already had an injury to his front paw from running down a hill over and over.. that healed and I thought it was a fluke. Yesterday he was running to the fence for a ball (no hill) and started screaming and holding his back leg up. He screamed for a full 2 minutes like he was dying!! I was terrified and held him until he stopped yelping. Within 3 minutes he was back to normal. He is fine today but we are taking it easy. I know he was hurt but the screaming was nuts. Could have a low pain tolerance ? Or does he need another vet visit? He is definitely a talkative little guy..