How do we know what our dogs are thinking? The answer is we observe what the dog is doing and we learn how to interpret his body language. A friendly dog will have a relaxed mouth, relaxed eyes and relaxed coat to name a few signs the dog is relaxed and happy. A dog that is excessively yawning, panting (without high temperatures being present), urinating, shaking or has a change in eye color is a dog that is stressed. It would be a good idea to remove the animal from whatever is causing the dog stress so that a bad situation does not escalate and become worse.