Gender prediction wrong???

Jade • Momma of a beautiful baby girl!💗 #2 due November 15th🤰🏼🌈first responder🚨🚑

So Im 19w2d and I had a 3D ultrasound at 14 weeks. She had a hard time finding the gender because little ones legs were closed. She finally said it was a girl and told me about the 3 lines. Ive seen the 3 lines before with my first baby but i dont see what shes talking about here. Any chance she was wrong? I just have this weird feeling that its a boy lol. Has anyone else experienced their gender predictions/determination be wrong?