How long should my arm be sore? Is there anything I can rub on the arm? Currently I am taking Alleve for a sore back. When the pharmacist gave me the shot yesterday, she said there was no bleeding and she might also have said no bruising. I can't really tell that it is swollen. My arm did not get sore until a few hours after the shot. I got a tdap shot with barely any pain and no problems at all, a few weeks ago.