Hi,
Welcome to health care magic,
Stomach pain,gas trouble,nausea,stomach fullness and
constipation could be related to gastritis or
gastroenteritis or some other intestinal issue but it must be evaluated further by complete medical history and thoroughly clinical examination with some relevant tests.
Without examination and tests it is very difficult to comment regarding diagnosis since all your investigations were perfectly alright.
Meanwhile,You can take some pain killers (
diclofenac) and antispasmodics (
dicyclomine) with antacids (
pantoprazole) available over the counter for symptomatic relief and continue with provera as your per prescription from your gynecologist and wait till your periods starts.
Also take laxatives or purgatives 3TSF at bed time for effortless bowel evacuation.
However he is advised to undergo routine blood tests with abdominal ultrasound or may be upper GI scopy again since it has passed almost 1 year of previous tests to rule out internal abdomen issue and to be in safer side.
So,you should see some local physician for complete evaluation.
Regards,