Hi welcome to health care magic... You might have done USG investigation to rule out gall bladder and liver problem... No significant pathology detected so it could be functional constipation problem that can lead pain... For that you can take digene like syrup for proper digestion.. If constipation more than ispghula with milk can be taken for few days .. Avoid gas forming foods like... -turnip -cabbage -cauliflower -onion etc..... Cooked oatmeal help in soothing stomach.... Avoid excess tea, coffee, smoking etc... If still no benefit than according to examination detailed evaluation needed and investigated accordingly... ..If still cause not clear than it could be from muscular strain problem Advise : physician consultation for examination... Take care