Lymphoma typically causes painless (and progressive) enlargement of one or more lymph nodes. On the other hand, tender, painful lymph nodes are usually caused by infection or inflammation.
Unfortunately, it is not possible to provide a specific diagnosis over the Internet to patients with concerns regarding enlarged lymph nodes. Therefore, my advice is for you to see your doctor for an examination. If you have persistently enlarged lymph nodes (and especially if they continue to enlarge), then a biopsy may become necessary to rule-out lymphoma, or other cancers involving the lymph nodes.
Sincerely,
Robert A. Wascher, MD, FACS
www.doctorwascher.com
Author, "A Cancer Prevention Guide for the Human Race"