I am super grateful to have gotten my booster (teacher) but wow it kicked my butt! Not sick enough to not work or anything, but I have had a headache for the past 3 days, soreness under my arm pit which has finally gone, and less energy than usual since I got the shot last Friday. I had just gotten over a cold-type virus, so I am sure that is part of it. Any headache sufferers here, and if so how long did it last? My workouts have been minimal, and I am fine with that until I get back to "normal."