Ultrasounds?

I had a scan at 6 weeks for spotting and then I kept my 8 week ultrasound for piece of mind. I went in at 11 weeks for my “nurse education appointment” and no ultrasound at that one. I go for what I believe is just a physical/pap in a few days where I will be 13+4. I read the papers and it says I could pay $75 extra and get an early gender scan at 16 weeks but if I choose not to do that then my I will have an anatomy scan regardless at 20 weeks.

My question is, don’t places usually do a 12 week scan? (I’m in the US by the way)