12 weeks gender scan

So today i went to see baby. She was calm at first but when the tech started probing 😂😂 she just went ballistic 😍. But anyway doctor said I’m measuring 1 week ahead and even tried to change my due date. She asked me if i wanted to know the gender of course i said yeah... she said it’s a girl but don’t quote her. I didn’t see a penis and being the mom of 4 boys i know what it looks like. So my question is could she really tel this early?