Hello dt.johnson1. I am experiencing the same thing except that it started when I decided to go from 60 mg/day to 40 mg/day about 8 months ago. A couple months later I started to experience tension headache like symptoms and constant brain fog. It feels like someone is squeezing my brain. I have swtiched to Prozac now because we thought maybe my body was just rejecting the Celexa after a number of years of being on it, but I am not sure if it is due to withdrawal or being on Celexa yet. Extremely debilitating.