The mystery of the swollen lymph node..words of encouragement please

So I've had an armpit LN that is swollen for almost a yr. When I found it I immediately went to GP. I went for an us/bloodwork per his request. Came back as nothing. I was pregnant when I found it so my ob sent me to a dr when it didn't change in size months later..had another us and mammagram. Came back again as nothing. So today I went back to my gp & he wants an MRI just to do a more detailed check. So I'm supposed to have this on Monday and I'm so nervous.I've had this for almost a year. Although I had tons of bloodwork through my pregnancy and now I've had multiple tests -- all saying it was nothing -- I'm nervous that the MRI could find something more. Aside from being pregnant I haven't noticed any other symptoms But I'm content that I've stayed on top of this. My GP almost couldn't believe the the dr didn't do something more than an ultrasound. Apparently us's can't always give the complete picture. Fingers crossed. Ladies stay on top of your exams..I'm only 30 and found this. If it is something bad, atleast I know I've stayed vigilant.