Enlarged Axillary Lymph Node

As the title suggests, I have an enlarged axillary lymph node. My doctor rushed an ultrasound and blood work.
The results were that it is a solid mass roughly 4cm in diameter. I don't know if this means anything, but the blood flow on the doppler was intense to this 'ball'. It did have clearly defined borders (which is a good thing, they said).

Due to fatigue, constant infections, etc. the doc ran a lupus test, which came back negative. Also, I had a 'left shift' (indicates neutrophils) with no infection at the time (just off antibiotics).

My doc wants a biopsy Monday, so all this has been rushed. I didn't even realize why she seemed so panicked about the lump.

It is painless, no swelling around it, just a giant ball in the upper part of my armpit.

Does this sound like lymphoma is possible? Probable? I am having my biopsy, but I want to be prepared for the possibility...

Also, how long does it take to get biopsy results back?