Chronic Abdominal pain started 2 days after D&C 7 weeks ago

41 yr old female with 6 previous pregnancies and 4 live births, symtoms (symptoms) began 2 days after D&C, wt. loss of 20lbs., diarrhea or scanty small diameter stool, abdominal pain upper left, upper and lower right and upper middle pelvis relieved by lying on rt side rolled slightly anteriorly or upon defecation, nausea, inappetance, severe pain 2-6 hours after eating, shortness of breath, sinus tachycardia when standing, ekg, ct thorax, VQ scan, throracic rads all normal with exception of sinus tach when standing, sitting or walking, sinus tach returns to normal after 20 to 30 minutes of laying down, all labwork incl. TSH and Free T4 normal, CBC & chem panel checked 4 times during 7 weeks, endoscopy revealed sliding hiatal hernia, gastritis, duodenitis with no causative agents found, "negative" barium enema caused tachycardia then severe pain at area where barium transit was retarded until pressure was increased as barium entered the sigmoid colon & severe pain in left rear groin and buttock day after BE and continues but not as severely, all cultures neg for salmonella, shigella, clostridium, parasite exams neg, carcinoid urine test neg., complete abd u/s neg, metoclopramide causes pain, symax seems to reduce pain, Patient on protonix 40mg BID & ranitidine 75mg QD, What ideas do you have that may help me get a diagnosis prior to exploratory laparotomy?