What Could On And Off Pain In Right Side Of Abdomen Indicate?

For the past 2 weeks, I have had intermittent right sided abdominal pain. (Never on the left side)Pain that is so intense at times that I can t stand up straight. It doesn t matter if it is after I eat or if I haven t eaten anything for hours. It normally happens in the evening. I had a CT with contrast a week ago and was told they could not see anything out of the norm. My bloodwork came back normal as well. Do you have any ideas about what could be going on?