Ultra sound not till dec 🤔

I went to the doc had my blood work done and we went over to expect and some questions I had. Got my blood work back today it came back normal and all good. But I’m curious as to why she will not give me an ultrasound till dec 16. I’m currently 4 weeks and 5 days. I asked her why and she stated “ that they don’t do ultra sound till at or after 10 weeks”. I’ve read that ppl are getting them at done 8 weeks. Anyone else have to wait a while month for an ultrasound?