For a right-sided headache, you can start with common over-the-counter pain relievers such as paracetamol or ibuprofen, taken according to the package instructions. Resting in a quiet, dark room, staying hydrated, and applying a cool compress to your forehead can also help soothe the pain. Please avoid triggers like bright screens, skipped meals, or stress. If your headache is sudden and extremely severe, or accompanied by symptoms like vision changes, fever, neck stiffness, or weakness, you should seek immediate medical attention. Otherwise, if the pain persists for more than a few days, please consult a doctor for a proper evaluation.