Hello and Welcome to 'Ask A Doctor' service. I have reviewed your query and here is my advice.
Well, a tender node is not always cancerous and can be due to infection..
As it is painful too, and it has improved then it is more likely to be infection only..
Jumping directly to cancer is not appropriate as every lump is not cancerous.
So you should take a 5 days course of antibiotics like
Amoxicillin or
Amoxi-clav and along with it take anti inflammatory painkillers like
Ibuprofen.
Do alternate warm and cool compresses over the node.
Do not manipulate it again and again as it can get irritated further and become more painful..
In case if even after taking antibiotics it does not improve then you can get an FNAC done.
For now nothing to worry about it, please keep updated.
Hope I have answered your query. Let me know if I can assist you further.