welcome to health care magic
In the query you didn't mention your age..
never be tender..cancerous lymphnodes enlarge in size in due course and they become matted that is they attach one another..
Swollen lymphnode above the right collar bone means it is infected..may be from oral cavity.you didn't mention about other symptoms..
But the presence since 2 months is the odd thing..
Consult Pathologist and have FNAC(fine needle aspiration cytology) and the report will tell you the exact diagnosis.
Dont worry about the cancer,,it is not cancer
hope you understand my suggestion