Hi and welcome to Health care magic.Thank you for the query.
In her age commony cause of abdominal pain
is gynaecological disorders so this is the first thing to rule out. fluid in pelvic may indicate pelvic infection
or ovarian cysts. the best way to evaluate this is to do laparoscopy
so if pain persists it should be done. Ohe possible causes are hepatitis
or gastritis and more detailed work up should be done to detect exact problem.
Wish you good health. Regards