Just a thought - have you had the Covid vaccine recently? A lot of people are reporting a swollen node in either the collar bone or armpit area and investigations have found them to be benign. They are starting to think that the vaccine is causing this in some patients & if it is, it's actually a good thing. Nodes swell to fight an infection (as well as for other reasons) and the body is reacting to a 'foreign body' being introduced into it so it means the person's immune system is strong & doing it's job - trying to repel invaders. I had a node appear on my chest the day after my 2nd vaccine. A fine needle aspiration biopsy carried out by my cancer consultant showed the node was benign so it's being put down to the vaccine.

Angie (melanoma patient)