Sound like symptoms of rheumatism. Try to keep body warm and not exposed to wind. Whether air cond or fan, the wind shouldn’t blow directly onto you. Drink warm water and eat warming food.
Hey, It might be because of the cold temperature because of the AC. Better would be to not the keep the room temperature very low and wear long sleeves so that your body is covered
You on the aircon? Try wearing long sleeves and trousers to sleep. Sometimes even sock if my ankle hurts. I have this problem too. Don't let the fan blow you directly too.