Hi McBub
Your shots are very similar to mine and I got girl guesses - but they were only guesses as full nub shot not clear.
My theory is that as our babies are measuring further ahead (mine was measuring 13wks 4 days too) the nub has already started forming into genitalia. Yes this very well may be wishful thinking, and I am absolutely no expert! But if you look through the confirmed girl nubs, you will notice that the girl nubs at 12 weeks are much more pronounced and once you get over 13 it is harder to make them out.
Perhaps a sono can chime in! I am still thinking about boy names and am half expecting a boy, but it's fun to think about the possibility of a girl.