Swollen lymph node. Of night sweat?

In one side of the neck I can find a pea size lymph node normally but when I stretch my neck putting my head in the opposite direction its becoming big like a mass which is hard is it the lymph node itself or not. I'm scared. Currently I'm having tonsils on the same side but I had this swollen lymph node this big a year ago also when I had another infection. I don't know whether that never went down from the previous infection of last year or not. Also since last one week, two hrs after going to bed I'm feeling sudden warmth and a bit of sweating that I have to remove my blanket ( since the ac stays on at 26) then I feel quite normal and after that when I get cooled if I put on the blanket again it doesn't feel that hot. Is it a symptom of night sweat? Are this the signs of lymphoma and I don't know for how long it is swollen ( if its the lymph node)