I am recently facing a problem in my neck, i think they are lymph nodes because they are a little painful and i am not sure whether and how these lymph nodes have been coming up. I am a smoker, i smoke regularly , i also smoke marijuana at times. The lymph nodes on my neck are there for the past 3 months. They keep coming and going. When I smoke anything it tends to swell up and gives tingling feeling inside my lymph nodes and when I wake up after sleep sometimes it swells down a bit. I once had the same problem long back , so I went to a doctor. He prescribed me something ( I don't remember the name of the tablets) but it worked very effectively.
I think it was some kind of a anti-inflammatory med. I'm also scared if they turn out to be cancer or a tumor. My father had cancer too but pancreatic. But people say cancer may run through the genes.

Please help.