Fetal echocardiogram

Just had my 20 week anatomy ultrasound and it took almost an hour, so I knew something wasn't right. The baby looked fine, saw the little fingers and little toes, saw her yawn and scratch her nose. But the tech said I need to go back for another ultrasound to get more pictures. The techs won't say anything to you here at all, but when she was telling the receptionist I heard her mention that the baby would need a fetal echocardiogram. Is anyone else going through this, or has had experience with it in the past? I am just beside myself with worry 😕