If your dog is in pain, it will show physical, behavioral, and mobility-related symptoms like: • Tightening of muscles • Its back may be arched • It may also try to duck its head below its shoulders • Your dog will also shake, pant, or tremble. • It will also moan loudly and won't like being physically touched. • It will be restless and may become aggressive at times. • A dog may also begin to limp or refuse to walk altogether. • It will also avoid climbing any stairs and may become lethargic.