Hey, i have 2 nodes in my groin and 2 nodes on the sides of my neck wich i know are normal for me to be able to feel, since i am very slim and only 16. but if i can always feel the nodes when pea sized, then how do i know when they become enlarged?

Lymph nodes are your body’s way of eliminating infection. They can persist days to weeks and should shrink with time. If they are small, usually no problem. If they are larger - say a peach pit, or golf ball, or even apple, they are activated and will subside when no longer needed. This is normal function.

Small,shotty,firm lymph nodes are remnants of an old burnt out infection or old inflammation. They shouldn't increase in size or new ones develop. If you have concerns, for peace of mind have your MD examine&advise you. A CBC&differential count and a mono test could also be performed.