Gender wrong three times?

Rachel
Maybe I am officially crazy. We had the Harmony test at 10w5d that said girl. An ultrasound at 16 weeks said girl. I saw 3 lines pretty clearly. Our anatomy scan at 20 weeks said girl, but the tech couldn't get a good picture like we did at 16 weeks. She kept saying it's a girl 100% but I still don't believe it. 
Has anyone been told girl 3 times and actually had a boy? I want to have a girl so badly but I'm so nervous to get excited!