16 week gender scan

16 week gender scan: had this scan done two weeks ago at 16 weeks elective, currently 18 weeks and have another 2 week wait until the anatomy scan at 20 weeks. Desperately was hoping for a girl, although thankful for any healthy baby, and was told girl at 16 weeks! I definitely think the scan looks like a girl as I was told but I can't help second guessing and wondering if it'll be wrong at the 20 week scan. Any opinions? I feel like we have a pretty clear shot...  Already have a 5 year old boy, really hoping this is our princess!