Wow, so glad I found this group! My dermatographia started 12 days after my booster. It is still severe 3 weeks later. I also experienced joint swelling and joint pain. Blood work showed high blood clotting and overall inflammation. I thought that perhaps the demeatographia was trigged by an infection of some sort, but after reading through these posts it sounds like the timeline fits with the booster. Any one else with joint swelling and pain?