Weight gain,top of stomach hurts,gas,sometimes low grade fever.sometimes nausa,zantac (ranitidine) helps temp.ongoing for couple of weeks..veryfull all the time?

Stomach pain: Upper abdominal pain responding to zantac (ranitidine) probably related to stomach irritation in the form of gastritis, ulcer or bad reflux with esophageal irritation. You might want to checked for stomach infection to eradicate the infection and the symptoms.

Epigastric pain/feve: May be gallbladder versus H pylori infection, could be hepatitis/ crhosis ascites, rarely mass lymphoma , less likely infected pancreatitic cyst ( would be more ill)or ovarian pathology.Would seek medical attention at doctor/ urgent care in ER may benefit from CT of abdomen/pelvis.