I was about 34 and stationed in Hawaii. I'd been boogy boarding at Sunset Beach (not bragging...just passing on the story) and was on my way back to base when I got hit. And I mean HIT. Worst pain I'd ever had. I pulled over to the side of the road, got out of the car, and rocked back and forth on my knees (and puked) beside the car. Then it went away! I thought, well that was weird...I must be dehydrated.
I didn't have another for nearly 5 years. I had retired from the Air Force by then and was driving back from Abilene when I got hit again. Same scenario. This time I thought, "well, this is it. I've got a brain tumor. I'll be dead in a year or two."
I went to see a local doc and, unlike most of the experiences here, he nailed it right on the first try. As a matter of fact, his exact words were "you're having cluster headaches. You poor bastard." I'd never heard of them and had to look them up.
I look back on how I felt with that second hit and kinda laugh...I thought for sure it was over for me. There was no way I could have pain like that without it being a tumor or cancer or some such.