I'm not sure how you came to the conclusion that it is cancer, since that is the least likely cause, particularly since it is a single lymph node. The most common reason for lymph node swelling is exposure to bacteria or viruses: https://www.mayoclinic.org/diseases-conditions/swollen-lymph-nodes/symptoms-causes/syc-20353902
This is certainly not cause for undue alarm.
Hi, I understand why you're concerned after reading about the infamous "Virchow's Node". Yes, it's so important that it's named. Enlargement in a left-side-supraclavicular node can be a metastasis from a hidden abdominal cancer (including stomach and pancreas), even with no obvious abdominal symptoms.
But it's not very large at this point. It's not "rock hard", right? I'm guessing you are young, so that lessens concern over cancer, too. Do you have a family history of cancer? Do you gave any internal pains? Fever?
The odds are high that it is just an infection, as Kirstie says. Keep an eye on it just to make sure it doesn't keep growing and growing. But it will probably go away on it's own. Don't keep pressing it, though, as the irritation can make it get a little bigger there.
Hello~First, the worse thing a person can do is contact "Dr Google" I know, I am an expert and it has gotten me in more trouble than I care to admit. It seems like only the worse of the worse is on there and it IS scary.
As to the lump, I was told that if it is soft and movable (not fixed and can't move), then in all probability it isn't cancer. If you are concerned however, then see your doctor or dermatologist, they will be able to set your mind at ease, they MIGHT, I am saying MIGHT do a biopsy on it to test for cells, but at your age, and the fact it is soft and moves, they probably won't they might just do some blood work or nothing at all.
Give it a few days or weeks, if it is still there, or growing and especially if it starts to hurt, then see your physician right away, and, don't press it, that will make it hurt even without it being anything serious.