Sudden Severe Headache
One minute you're fine and the next – bam! You have what feels like the worst headache of your life. This could be a sign of a ruptured aneurysm, or weakened blood vessel, in the brain, which can quickly cause a life-threatening hemorrhage. If you have this kind of severe 'thunderclap' headache, don't wait to consult with your doctor – rush to the hospital as soon as possible.