Another couple of weeks passed, I still had this headache in varying strength every day. It got so bad while I was waiting for the blood test results, that one afternoon I walked into town & into opticians until I got seen. A great opthalmologist at Specsavers listened to my woes, did a full set of tests & ruled out an infection or a return of my Graves. He did note a nevus (freckle) on the back of the affected eye, which I don't believe was there on any of my previous eye tests. This would not normally be a problematic growth, but it was close to my optic nerve and he wondered if it was pressing on it and causing the pain. He referred me to a specialist at the hospital, and did some further field of vision tests, which he said would determine how quickly I needed referral. It turned out I didn't need an urgent referral, so he commiserated and said it would take a few weeks for my appointment to be arranged.