If clear po sa ultrasound, like maayos pwesto ni baby para makita, then yes, accurate. Fully formed na po yung genitals nila at that age. But don't worry po, gender disappointment is a very common thing among expectant mothers. Ako rin medyo na-let down saglit nung nalaman kong boy pala first baby namin. But it doesn't mean you're bad or you won't love them. Initial reaction lang naman po sya ☺️
Here's a useful article about it :)
https://www.parents.com/getting-pregnant/gender/prediction/the-boy-girl-blues-dealing-with-gender-disappointment/
Andy