Sounds like it might have been just the sentinel node biopsy Fiona - though I could be wrong -?and don’t worry, this is all new to most of us!
Hopefully they did an imprint/frozen section during your surgery - if they do it while you’re still asleep then they can decide whether or not the lymph nodes seem to be cancerous and then remove them in the same operation. But I don’t know if this was the case in your surgery or not. I’m hoping it’s a good sign for you that maybe they didn’t need to take any more. All the best for Friday.