I Have Had A Swollen Lymph Node (well That's What

I have had a swollen lymph node (well that's what I think it is on my right side of my groin (female 30yrs old) I have had cramps outside of my cycle in my abdominal area for months now on and off now I have symptoms of nasua and lower back pain all the time, I have been checked I'm not pregnant. I have had a cyst on my ovary a long time ago before my first pregnancy back in 2004. What is going on.... My doctor says it's nothing to worry about.