Only get one ultrasound??

Olivia • Mommy to a baby boy 💙
I just got my bfp, called an obgyn this morning and made an appointment. I have an appointment at 7 weeks and 10 weeks, neither are ultrasounds. They told me I'll have one ultrasound at 18-20 weeks. Is that normal?? I had a miscarriage awhile back at 8 weeks, so I'm really wanting an early ultrasound to make sure baby has a heartbeat.