Confirmation test

I tested positive for a urine test about 3 weeks ago. At that point, I called the doctor to set up my first prenatal appointment. She set me up for a confirmation appointment if I wanted to do that. I called back to cancel that cause I didn't really care to waste money on something I already knew to be true. So I called back and said that if it's not required to do that, I'd rather just set up my first prenatal appointment instead. So they did. I keep seeing people post about the confirmation tests. Is it something that's generally required or is it different doctor to doctor? My first prenatal is on Tuesday. Just hoping I'm not missing a vital step.