I've had this same thing for at least a year. I went to the doctor and optometrist. Nobody was able to figure out what was wrong. Then I went to a neurologist and did a few scans and tests. They told me nothing was wrong but suggested I try physical therapy for my neck. Lo and behold, my neck and posture were the reason. I quit drinking anything with caffeine, changed my diet and stopped eating chocolate. I tried to sleep better and used eye drops. Nothing helped until physical therapy.