How accurate

Bella • 18 years old❤Due date 11/02/2015 ❤
So I went to my gyni at 19weeks and he said he was pretty convinced it was a girl but will "confirm " at the next app....It's making me worry because what if I go back next time and he says it's a boy instead!!!He didn't give me a photo of her parts so I can't even go back to check !!please help.any advice/stories