Hello! Thank you for asking on HCM! Your symptoms could be related to the viral infection or occipital neuralgia. Although it is not typical of occipital neuralgia that the pain is triggered by standing up position. Intracranial Hypotension could cause such symptomatology. Anyway, I would recommend having some rest and taking plenty of fluids in the next days. A close monitoring of your blood pressure is also necessary to exclude low blood pressure. But if your situation does not improve, I would recommend consulting with your doctor for a physical check up, a brain CT scan and a complete blood count for anemia. Hope to have been helpful! Kind regards, Dr. Aida