Hi ! Many times chronic granulomatous condition of the intestines or abdomen continue to give rise to pain abdomen, which is not easy to diagnose even with all the investigations. How is her weight ? Is there any recent loss of weight and associated fever specially in the evenings. You have to discuss with your treating doctor on this issue so that pertaining investigations can be done. Also a serum lipase test may be helpful. There is no harm in giving her a dose of deworming drug even if the stool test is negative. If everything else comes out to be negative, then you may have to consider and give a trial to anti anxiety drugs only after consulting your family physician. Wishing your daughter an early recovery.