I don't see any clues in the new pic, but I'm still thinking pink.
I believe you're getting boy guesses because of baby's position. The baby is sort of curled up and the rump is obscured, and I'm pretty sure that's causing the nub to look like it's showing a bit of a rise. Even so, boy nubs are much more sharply angled than this by 13 weeks. I think if we could see the end of the spine properly the low nub angle would be more obvious. The only thing that would change my opinion is if your baby is measuring several days behind.