Turns out it was just a cyst.. so there is nothing at all to worry about, except taking the stitches out..
I'm going to bring Emerald in tomorrow for a follow up on her bladder infection, to get an accurate blood sugar reading, and her vaccines. Now the question is, should I booster her FeLV vaccine?
(update 2016 - "FIP titres" are a waste of time and money don't do them. They are pointless.)