I have a groin lymph node that has been swollen for 3 weeks. the doc said it was fine a few days after it popped up but it's still here.?

Have it looked at...: Details are needed in your case in order to determine why this is happening- was it tender? Matted? Had. Associated symptoms? It's more appropriate if this is done in person with your primary care doctor.

Monitoring Centers: Lymphatic system absorbs/carries things too big to go into the arteries/veins like bacteria eaten by white cells and digested food. Lymph nodes "taste" the lymph for anything bad like bacteria/viruses/cancers, etc. When it detects a problem, it alerts the immune system and your body reacts. They enlarge in response to the inflammation they create when they react. They shrink when all is well.