When you go to decent optician it not just the quality of the eye test but ensuring that the glasses you need are those you get. 20 years ago I got headaches, went to a number of the usual names and ended up nowhere. Finally went to a quality small opticians with two partners and immediately had the issue diagnosed. My prescription is complicated and each visit needs tweaking but I remain headache free. Further, when I spoke about shooting and getting contact lenses to help the right lenses were sought with the right advice - it was a combination of the two. My bill every 3 years or so is £1,200 - not cheap but its £1 a day - you would quickly pay that for quality glasses and no headaches.