If the doctors couldn't find anything then there likely is nothing. Because you are worried that they might be wrong, your anxiety is playing tricks on you and making you study your body looking for clues that the doctors are wrong. The more you study, the more you notice and you keep adding them up thinking they must surely be wrong.
Many people on this chatline have been where you are and end up going to ER thinking they have a heart attack only to find there was nothing wrong except their anxiety working up their fears. I went once but when the doc said if I had those symptoms for a few days I would be dead, then I instantly forgot about them and felt fine.
It isn't easy for some people, but until you do accept the diagnosis you were given, you will suffer from anxiety and think these meaningless pains are signals. Everyone gets them, but ignores them unless they have anxiety plugging up their thought processes because no one wants to die, so they can't get it out of their minds. Very natural thoughts when you don't trust the diagnosis.