Only ultrasound at 20 weeks?

B

I just had my first visit with my GP today at 6w2d. I see the OB at the maternity clinic around 10 weeks. My GP said I don’t need a dating ultrasound because I know the first day of my last period so I won’t get an ultrasound until about 20 weeks. Is that normal? I kind of expected one sooner to see if there was a heart beat and only one etc!