Hi. Thanks for your query, albeit short and specific. Noted the history and understood your concerns. Muscle cramps with a hard knot which dissipated on abatement of pain can be a muscular knot. Hence to know whether this is hernia or not I would advise you the following: Put a palm on the affected area and cough hard, if there is an impulse or bulge on coughing and that the lump is getting reduced on pressure this is most probably a hernia although right upper abdomen is a rare site of hernia unless you have got operated in this area or got some trauma in past. This also can be confirmed by a high resolution ultrasonography and CT scan which may be needed to know he depth and extent of the problem. If the hernia is confirmed get an appointment for surgery.