19yrOld teen, abdomen painsevere. Gallstones. Diagnosed w ulcers. Has had CT, HIDA, endos/colon. Fullness, can't eat, fever off/on, shakes, flush face, miserable?

Fever. With presence of gall stones you may have gall bladder disease . Yo should see your doctor for treatment.
Cholecystitis. With the diagnosis confirmed with the test procedures listed, it looks like you need to consult a GI specialist for medical treatment before surgery for the ultimate cure. Most likely you may need to be treated as inpatient with a combination of IV antibiotics and IV fluids. Pl let us know if you need a referral.
Complex. Too complicated and not enough information to discuss in this forum. Best to discuss with your physicians, and don't think twice about getting a second opinion.
If he cannot. eat anything and has fever, she needs medical attention. Take her to emergency room if an appointment with her doctor is not possible in next 1-2 days.