#1 – Sudden and severe headaches
Doctors don’t worry too much about the headaches that come gradually, but the ones that come suddenly and severe are the ones you should worry about. They call it the Thunderclap.
That throbbing pain could indicate a burst blood vessel and aneurysm, and it can be life-threatening if it occurred in the aorta because it can grow and weaken the blood vessel causing it to rupture. Also, if a headache comes with a stiff neck, then it could mean meningitis.