Here's the problem with forums. You know nothing about the OP other than what he chose to tell you. Part of what he chose to tell you is that he's had headaches all of his life. What in the world does it have to do with testosterone? You know nothing about any work up that he's had. Has he had an extensive work up or has he just seen one probably bad neurologist? We know nothing about the details of his past medical history other than he has a history of headaches. So the point is, is that it takes a lot of detailed analysis to formulate a differential diagnosis and then you work from there. You can't do that from a simple post on a forum. And in case you don't realize this there is no cure for aging and the degenerative conditions that go along with it.Apparently, you haven't experienced yet a degenerative condition associated with aging, that contemporary medicine has no clue how to cure, it just "treats" it. When that happens, you belief in the "medical literature" will quickly evaporate.
So not to derail that thread, please tell us, what is "out there" that we can't find with Google, which explains the OP headaches. Find the root cause according to the "research" and save us the neurology hand-waving nonsense that his "nerve endings are just too sensitive", clearly tied to migraine drugs that just cover up the symptoms, not identifying the true cause and clearly not curing or understanding anything.
But in a simple nutshell if he finds that injecting testosterone triggers a headache (headaches he has had his whole life) then don't inject testosterone. Use another delivery method. But what I also find interesting is that what triggered his headaches that he's had all his life before he started testosterone? Why does it have to be E2 or the ester? What caused it before that? Here we are trying to blame testosterone or hormonal on something that he's had his whole life before he ever started testosterone. From his post it also doesn't appear that it happens all the time. Is it an association or is it true causation?