I woke up with a headache this morning round about 9am. it got worse through out the day the pain continued till about 4pm i then took 1 mybulin and went to bed. what could be the cause of such an excruciating headache lasting so long.

Headache: Headaches are common. The most common types of headache are tension, migraine or sinus. Tension headaches are usually described and a "band across the head". Migraines are usually associated with nausea and a degree of visual impairment. Sinus headaches are typically associated with congestion and often a fever. Headaches from aneurysm are sudden and associated with photophobia.