Hi Hickory. Sorry to be flippant about the differences. Mine really are distinct and it sounds like some people have more gray areas around the 2 headache types. I think initially I said I had migraines because it hurt a lot and that was the only headache I had ever heard of that hurt a lot. By the time your head hurts for long enough to scare you, we go to a doctor and it is a mysterious pain and then our cycle ends, we feel better and assume it was allergies or we got a new prescription in our eye glasses and away we go, everything back to normal. 2 years later same thing, back to the eye or allergy doctor blah blah blah and 6 years later we finally realize it is none of these and maybe not even migraines and then our cycle starts and ends again without seeing the right doctor and we are still unsure. That was more or less my episodic history.
Now on to your migraine differentiation question. I feel I get a classic version of both migraine and CH. With a migraine I usually have a very small headache, barely enough to notice. 10-30 minutes later I get some visual flashes,spots, floaty things dancing around in my vision. At that point I stop what I am doing, take some aspirin and lay down in a dark room for a nap. If I do that my migraine will dissipate and be very subtle for a day or so.
If I miss the aspirin, lay down trick the migraine will build to slurred speach, major headache, nausea, sometimes vomiting and sometimes tingling limbs. I don't miss much because it hurts too bad. After experience with both headaches, it really is a different pain for me. But you have to have enough of both of them to feel it. I get 1 or 2 a year of these and I can't tie them to a specific cause.
My cluster cycle starts with a classic week or 2 of shadows at which time I now abort the cycle via techniques on the clusterbusters website. If I miss it each of my CH attacks start in the morning around 10am with excessive yawning usually before a hint of the pain, excessive heating of my body causing sweating, droopy eye, clogged sinuses (always left side), intense pain, sensitive top of my head (somewhere, search for the sweet spot and apply pressure to help with pain), rarely nausea but depends what I just ate, and always a trip to the men's room for a large bowl movement (you asked

), and it's the best one of the day but I am usually kipping pretty big by then, hunched over with my head in my hands. No sleep possible. Last for 30-60 minutes, only 1 per day usually, cycle lasts a few months.
Tried allergy medicine and pain relievers on the CH, no work, and once I figured out that the excedrin worked but the other pain relievers didn't, I started taking caffeine pills instead, same result if caught early enough.
Anywho, long winded, sorry everyone but it took me 20 years to figure this out and now I am on to new medicine and figuring that out too. With great success I might add.
Good luck Hickory, keep at it.
--Shaggy