I just went to pet a sleepy Barley, and when I pet him, he pants short and hard. His stomach heaves, even. He seems to be smiling, though, and his nose isn't stuffed or anything. Is he having breathing problems? Do dogs pant when they're happy, even if totally at rest? Am I paranoid? Although he's a chow mix, he has a long snout and shouldn't have sinus issues. Hmph.