I got the pertussis vaccine a couple days ago and last night noticed a tender, movable, hard, ball just above my collarbone.  I remember this happening about 10 yrs ago when I got a flu shot in the same arm, in which I had a soft tissue injury in that shoulder just before the injection.  This time the ball is much more sore.  Could it be a single lymph node, building immunity?  Is this common, and should I see a doctor?
Hi, Welcome. Based on the facts of your query-You seem to suffer post-pertusis shot Lymph node amenities, with reactive hyperplasia. And is a known body reaction. Nothing to worry. Show it to your doctor only if it persists with symptoms after 1 MTV. Hope this would help you to plan further treatment with your doctor. Will appreciate your Hitting thanks and writing excellent review comments to help needy patients like you. Welcome with any other further query in this regard. Good Day!! Chat Doctor. S. Genl-CVTS