2 vessel cord + gender

So I had my first ultrasound yesterday (currently 19w4d, first pregnancy) and the ultrasound technician said the cord has only two vessels. I got a bit scared when she said it and been a bit stressed since. Has anyone experienced that and how did things go afterwards?

Also she said it’s a boy. Is there any chance she could be wrong? I wanted a boy, but she wasn’t being very clear about it and didn’t talk much through everything that she was looking at with us and that concerned me.