10 signs that your cats may be in pain:

1. increase vocalization.
2. Licking a particular area of the body more than usual.
3. appearance of the nictitating membrane (the third eyelid)
4. Hiding
5. Panting or open mouth breathing.
6. Irritability or grumpiness ( from a cat who normally isn't that way)
7. Lack of appetite.
8. Change in mobility ( signs of limping or reluctance to move)
9. Change in litter box habits.
10. Increased clingy/ need-type behavior.

Done By: Siti Nur Rabiatul Adawiah Bte Mohd Sobrie

Credits to: http://www.catbehaviorassociates.com/10-signs-that-your-cat-may-be-in-pain