Has anyone had a 'concerning' ultrasound??

Megan • 27, married and expecting our second baby in June. My son Noah is almost 3:)
I'm new to this app- just got it today but I'm seriously trying to ease my mind so if anyone has been through this your thoughts would be so appreciated. We had our 12 week ultrasound a few days ago and everything seemed normal. Until the doctor called me a few hours later. She said the radiologist had examined my ultrasound and needed to send me in for the genetic bloodwork immediately. It takes a friggin WEEK to get the results back for the blood test so I'm over here just stress eating donuts like my life depends on it. This is my second baby, my son (3) was always normal ultrasounds. Has anyone else had a questionable ultrasound? How did everything turn out? Is anyone else going through this? Thanks guys:)