Symptoms of PMR started 24 hrs after receiving my third Covid (Phizer) booster. Severe arm, neck, shoulder pain came out of nowhere. Completely immobilized me and had to simply sit in a chair and not move. I’m a healthy 67 year old man who does daily yard work, walking 5 miles a day. Trying to describe what was happening to me was difficult. Remember saying that I felt like something had possessed my body.