It sounds like you are describing a dull achy abdominal pain below the abdominal. You already had a CT scan
which would have showed the appendix, and colon clearly. Abdominal pain could be caused by many different things. The region that you have pain is located in region where the the bladder, colon, and uterus (if you are a woman) are residing. Constipation could cause a dull achy pain in that region. If you are constipated, you can eat more foods rich in fiber and see if that relieves the problem. You could have a urinary tract infection where the bacteria are growing in the bladder, causing a condition called cystitis, which is inflammation of the bladder. People who have this complain of suprapubic pain and increased urinary urgency. It is also possible that you could have a STD
that is causing symptoms in your reproductive organs. You can make an appointment with your primary care doctor
to have your symptoms reevaluated. They could simply run some urine tests which would rule out any infectious cases, including STD's. If you are a woman, you can also make an appointment with your obgyn, and see if you need a pelvic exam. Again, please speak with your doctor about this concern.