Have you had a pelvic/abd ultrasound? It would show if there were any kind of cysts, lesions, or adhesions.
not too scare you but maybe you should get a colonscopy and make them check for polyps
I presume you are asking if there is a neurological cause to your abdominal pain, as this is a neurology and neurosurgery forum
There are not many neurological conditions that can cause abdominal pain and nausea, more commonly these symptoms are due to non-neurological causes
Migraine can cause abdominal symptoms such as nausea and vomiting and potentially resultant pain. There is usually a good history of headache, and migrainous features from an early age.
Although very rare, acute intermittent porphyria is a genetic condition that can cause attacks of acute pain, and also neuropathy or psychiatric disorders. It can be tested for by a blood and urine test.
Pain that localized to one area can in fact be from a problem in a different area, due to the layout and connections of the nerve pain fibers, termed 'referred pain'. Pain in the right lower area of the abdomen could potentially come from the upper abdomen or pelvis also.
I cannot substitute for a formal medical opinion, so it is very important to keep following with your own doctors.
Check out your gall-bladder. Maybe you have some kind of gallstone.