Lymph nodes can stay somewhat swollen your entire life if they react to some sickness or infection might get. I have two, one on each side of my neck which I can palpitate every single day and it's been like that for the last few years. I found one near my groin last year and it eventually got smaller after a few months. It can take some time for these things to go away. I wouldn't worry too much about it, if anything, get a second opinion and leave it at that. :)
and I agree with Dje, the mind is extraordinarily powerful indeed.