Limping or favoring a leg
Reluctance to move, jump, climb stairs, or play
Whining, whimpering, yelping, or growling
Panting when not hot or exercised
Restlessness or inability to get comfortable
Hiding, withdrawing, or unusual clinginess
Changes in appetite or drinking
Licking, chewing, or biting a specific area
Stiffness, especially after resting
Trouble standing up, lying down, or sitting
Tense body posture
Ears pinned back or tail tucked
Sensitivity to touch or being picked up
Changes in sleep patterns
Aggression or irritability when approached
Shaking or trembling
Excessive drooling
Unusual facial expression, such as squinting or a furrowed brow
Accidents in the house or difficulty using the bathroom
Changes in breathing or heart rate