Pulling pain in belly button. Went away with advil (ibuprofen). No longer hurts but still pulling. Daily nausea & dizziness. Abdominal ultrasound and X-ray clear?

Try pooping. A general rule in medicine @ your age says the closer the pain is to the belly button, the more likely it is to be benign. You could be getting a bowel obstruction, especially if you have a history of constipation or low fiber diet. There are plenty of other things it could be, but this is usually what i find. Try a gentle laxative and/or increased dietary fiber.