we can feel pain of body and we take necessary action to eliminate that pain through some medications or rest of body but the thought of "I" is the main problem because when you think that you are in pain instead of body is in pain.. pain multiply itself..and all unnecessary thoughts like "Why I am in pain?" , "Why this happen to me? ", "I am so sad", "Why other people are living so great and I am not like that.." etc.. Starts. so only non-acceptance that is unhappiness and that it is only acceptance that is happiness