Gender?

Ashley
So I had a 20 week ultra sound was told it was a boy, then week 25 I needed an ultra sound to check on the baby growth but my insurance doesn't cover ultra sounds so my friend whom is an ultra sound tech did a scan in me and thinks I'm having a girl has anyone had an ultra sound and the gender was wrong? I trust my doctors but my friend def also seemed like she knew what she was talking about. One confused mama