I think I may have asked this before on the forums as it's been years since this happened but I have a...mildly irritating condition coincidentally after trying to open my third eye. Honestly, I have always been horrible at meditation but while on vacation years ago I was performing chakra meditations and simultaneously got sick due to of all things an air-freshener. I was specifically focusing on opening my third eye at the time and ever since I've had mild(was worse originally as I've gotten somewhat used to it) sinus like pressure on my forehead. I've also always had bad sinus issues so I truly believe it's a coincidence but following that I had even more trouble meditating as the feeling felt worse when trying.
Years later it's pretty much just become part of me though I don't even try meditating anymore. I know pressure in your temples is a sign of opening the third eye and while if it is related I don't think I can do anything as I continued trying to open my third eye as well as all of my chakras for some time after that yet with no change though my curiosity has me wondering if the two could be connected.
Third Eye Side Affect?