Never been diagnosed. They are not as bad these days as they once were. They're always over the left eye and are like some of the symptoms in your link, but as I can manage the pain with the codeine I think it's not as serious. There is no obvious reason or trigger. MRIs didn't show anything wrong, nor eye tests.
@BrynCP
At least it is manageable then.
My poor wife started getting really bad headaches back in the early 90's and initially they were diagnosed as Migraines. As the years went by they became worse and were eventually diagnosed as Cluster Headaches at the Neurology Hospital in London.
It is closely linked to your Circadian rhythm and many suffers get the symptoms at a specific time of the year/week/day etc. My wife has 3 weeks worth at about midnight to 2pm every 18 months-ish.
Some poor souls have them every day.
My wife self-injects now and the pain is much easier for her to manage. I have, in the past, found her out back sobbing and banging her head on the patio to try and relieve the pain. If this sounds extreme then some of the things sufferers do on the CH forums she belongs to are beyond belief and are not for the squeamish.
Her pain is right side just behind the eye and she best describes it as a cross between a heavy blow from a hammer and a burning sharply pointed poker.
Horrible thing and doctors categorise it as probably the most extreme pain suffered for a medical condition.