Ahhh I understand your worry la, honestly, scan accuracy depends jugak on the sonographer's skill and baby position at 25 weeks, tapi usually at that stage dah quite reliable untuk identify gender lah. A few of my mum friends dapat boy scans yang confirmed boy when they delivered, but ada jugak one who kena surprise element because the angle wasn't clear enough that day, so it happens sometimes! Best thing is during your next scan tanya the sonographer ulangi confirm, and tell them you want to be 100% sure if gender reveal is important for you, okay?