My OB wants to see me again in 4 weeks

I had my first ultrasound last thursday at 13 weeks pregnant and my OB said everything looked normal so far. At the same time she took my sample for the NIPT (which hasn‘t come back yet). I asked her if I should come back for the anatomy scan and she was like, no I‘d like to do another ultrasound before that, in 4 weeks. Why would she want to see me again when everything looked good? Is she not being honest or just trying to make money? I‘m a little worried now that my baby is not as fine as she said!

Just to add, my regular blood work came back great (no deficiencies whatsoever). I only have severe nausea but I didn‘t even lose any weight, so this can‘t be the reason. Baby is also measuring a few days ahead. The nuchal translucency scan looked normal!