I woke up with one today.
The temp is going to 95 again today and I tend to get them when extreme weather is happening (fronts moving through, extreme heat/cold, 30-40 degree swings in temp in a single day, etc) - so spring and fall are the worst times for me.
The whole top of my head aches to the point where it's making me nauseous.
I only have 1 cup of coffee in the morning (sometimes it helps, other times not).
I have no other caffeine input (no soda, no chocolate, no teas with caffeine).
Tylenol is not helping any today and I'm sipping water slowly.
I might try a heating pad on my head and/or back of my neck - it sometimes helps.
Some days there's not much I can do but take something to knock me out (Nyquil or Benadril or Tylenol PM) so I sleep through the worst of it.
I suspect it's a type of migraine headache but since it usually is bad only a few times a year I haven't bothered seeing a doctor about it so far.
I hope you feel better soon.