The lymph nodes are part of lymphatic system. These are small swellings containing lymph and WBC and present all over the body . Thyroid glands if infected cause swelling of lymph nodes of neck and groin.
Yes, there are lymph nodes in almost every place in your body and thyroid problems can affect the lymph nodes in your groin. Try not to touch the swollen area because it will only irritate it more.
Pain in groin area, only hurt when seated.