Ultrasound Confusion

So I'm 15 weeks will be 16 weeks tomorrow. I have been Wanting to see my baby for the longest I had an ultrasound around 11 weeks but I'm ready to see my little snuggles again! It's really getting to me that my doctor told me that I needed to wait until I'm 18-20 weeks when they do the anatomy scan but I don't want to wait that long. I've been reading some people don't have but 2 ultrasounds their whole pregnancy and some have them every other week.