Hi ! From your immediate symptoms, it seems that your viral pneumonia has got a super added bacterial infection and has turned into a bacterial pneumonitis ending up in pleural effusion with pleuritis on the right side. This may be the reason for high fever with chills, pain mostly on the right side of upper abdome. The head aches may be due to fever. Another possibility is a acute on chronic cholecystitis with gall stones although it is less common in this age group. Both of the above can be diagnosed with help of X-ray Chest, and ultrasound apart from routine blood tests. If bladder infection is already diagnosed, then it has to be treated with appropriate antibiotics by your doctor. A sub hepatic appendicitis is another diagnosis which is worth considering though less common. This can be diagnosed only when the patient is examined by the doctor during the time of attack and also with several investigations. So I would suggest you to consult your family physician/general surgeon for this. Hope this helps you in managing your treatment.