Hello. Girls, I need advice about ultrasound. It will be 20 weeks. I h…

Hello. Girls, I need advice about ultrasound. It will be 20 weeks. I have hypertonus from 11 weeks. At the ultrasound at 18 weeks, it's also there. The sonographer said that the hypertonus hinders the baby from even moving. He recommended an ultrasound in two weeks. His equipment is old and he is old too. I decided to go to a private paid ultrasound for a check-up of all organs and to find out the sex. What kind of ultrasound should I go to, regular, 3D or 4D?