what can happen if i have a bad headache
Migraines may: 1  Cause pain that is moderate to severe and may pulsate. 2  Cause nausea, vomiting, or increased sensitivity to light or sound. 3  May affect only one side of your head or may affect both sides of your head. 4  Worsen with daily activity. 5  Last from four to 72 hours without treatment.