Hi welcome to health care magic... Your CT scan and blood report normal that suggest no specific organic cause present and chance of infection is less... Here your refractive error should be checked again and accordingly spec wear if change in refractive error.. Avoid stress and constant work on computer if applicable as it can lead tension headache... Get examined your ear if needed.... Try to avoid constipation as it can lead headache sometime. .. Rhinitis, dental problem like referred cause should be ruled out.. Paracetamol SOS can be taken.. Take care Advise : Physician consultation for examination...