I am under extreme anxiety at present time. The back of my head, not the neck, feels like it is in a vice, I mean really tight. Even making my vision sort of blurry. Has anybody ever had or have this symptom? I take 1 ea 100 mg of Zoloft in the morning but this comes on more as the day goes on. I am retired so it is not stress from work. any help would be much appreciated. Thanks so much.