Very Sorry about the mistaken diagnosis. I went through that as well. I had my swollen lymph node diagnosed as the MUMPS. Given the fact that I was 50, had had all shots for mumps, an early childhood experience with mumps, and Military shots along with another series of shots for all those diseases prior to living in Bolivia for four years....still I was diagnosed with Mumps. 3+ months later they finally took a biopsy and stage 4 cancer was the diagnosis.
It is too easy to say that those things happen or too hard understand what or why a diagnosis was the way it was. The point is now that you begin the fight against what is happening in your body.
To that I give my encouragement.