Hi 30bt, sorry to hear you are going through this. I had almost exactly this done in May 2011 (primary melanoma on back, 3 nodes identified, 1 groin, 2 right axilla).
It is hard to recall exactly how I was. I know that the sites of the node removals tended to sting quite a bit, the excision site on the back was not too bad at all, just a bit tight. I had mine done as day surgery, and I don't think I was under a full-on deep GA, because the procedure didn't go overly long. I'm pretty sure I was done on a Friday, and was back to work perhaps the Weds or Thurs following?
Just remember it isn't only the anaesthetic that affects you, this is a really emotionally draining thing, being told you have something potentially nasty that has to be dealt with by some fairly significant surgery. Even though you might think you've approached it without too much anxiety, deep down it's probably acting on you.
My results were through in about a week, maybe 8-9 days.
If you want any further information or just want to talk please feel free to PM me.
All the best,