My doctor scheduled my first dating scan at around 7 weeks of pregnancy. It's best to call your clinic, and they will tell you the perfect week based on your last period date.
I had terrible morning sickness right from week 5, and my doctor booked my dating scan at 7 weeks to check the heartbeat. It was a relief to see the baby was doing fine despite me throwing up constantly.
Go around 7-8 weeks, because going at 5 weeks usually just shows a tiny sac and then you'll spend two weeks googling in panic! Wait a bit so you can see a proper heartbeat.
I felt so many emotions during my first scan at 8 weeks! Hearing that tiny heartbeat for the first time made everything feel so real, I actually cried in the clinic.
I panicked and rushed for a scan at 5 weeks, but we couldn't see the heartbeat and I was terrified. Went back at 8 weeks and everything was perfectly normal. So wait till 7-8 weeks, it's much better.