I have a swollen lymph node in my neck, it's been there for years, it's not protruding, but when i press on it i know it's swollen. why?

No growth-no worries: Lymph nodes are the body filters to remove infections. As with filters in you car and home, used filters cannot be made "like new," even with extensive cleaning. Similarly, lymph nodes that have participated in an infection are never "new." They remain somewhat enlarged. We become concerned when a lymph node is growing in size, particularly in the context of an illness, as this may be lymphoma.