12w 5 day with generic results

I went in for my 13 week follow up and got my ultrasound done, when we went for the genetic testing review the 5 main things they tested came back less than 1%.... but when they did my ultrasound they said baby’s neck was measuring 3.12 and are referring me to a Hugh risk OB to see what’s going on... my mind was in shock and I wasn’t prepared to ask questions. Like what could this mean?... what’s the “normal” size ?.... what are the next steps?.....

Anyone have any insight on this?? Baby moves around a lot and I was told out of the 3 measurements that 3.12 was the biggest one. Could it be just the angel of the ultrasound machine???

Thanks xoxo