its not the fact that its homegrown that is causing a headache, cause i mean if you think about it just about all weed is "homegrown" in some way or another. It's just how that type of weed is reacting with your body on that certain day. I've gotten a headache from shit mids but also good stuff like kush. So it just depends really, you could get a headache from just about anything depending on the day.