Gender mistakes ? 🤔

I had an prenatal appointment today and my ob usually lets me see the baby just for relief .. I am 18 weeks today and couldn’t get a clear picture because the baby was doing some sort of yoga position with its legs over its head and moving around like it just had a cup of coffee 😂 ... but she said “your baby looks like a boy” and pointed at the screen at I don’t know what because the position was so confusing.. could it be possible that it could be the umbilical cord she’s seen instead ? She did tell me to wait until my official anatomy scan which is on the 28th.. has anyone Ob ever gotten your babies gender wrong or know of someone who has gotten their gender mistaken before the official anatomy ? (I hope she’s wrong 😩)