Lymph Node that changes in size?

I have a lymph node that has been "acting up" for nearly a year. It started with an ear infection last August to be exact. Ever since it swells off and on. When it's really swollen it hurts and usually coincides with ear ache, sore throat and sometimes general sinus symptoms. I am just wondering if this is a sign of lymphoma? I would assume that with cancer it would probably remain enlarged all the time or continue to get bigger. I've also read that lymphomas usually involve more than one lymph node. Any help or insight is greatly appreciated.