I am sorry to hear that you are in so much pain. It is important to consult a doctor immediately to rule out herpes, pleuritis (inflammation or infection of the lining of lung), pericarditis (inflammation or infection of lining of heart), an abscess under the diaphragm bad gastric ulcer, or a spleen abscess. You may need ultrasound of the upper abdomen, chest X-ray, ECHO etc. A comprehensive investigation is required keeping all the points in mind. Do discuss this with your doctor and get yourself examined. Take care!