HCG Test- once or twice?

I have heard from a lot of people that they get their hcg blood test done twice, once when they first confirm pregnancy and then again two or three days later to check that the levels are rising properly.

I have my levels checked 11/4 and the doctor called back saying I don’t need checked again and that we can set up my ultrasound for Nov 27th.

Can I call and request a second blood test just to double check that everything is okay? This is my first pregnancy and I have really bad anxiety and am worried something is wrong. Thoughts?