Abnormalities found on ultrasound

We had our first appointment on Monday. I thought I was 7 weeks but when I saw the ultrasound, the baby looked much further along than that (I'm thinking now about 11 weeks). The doctor found some abnormalities on the ultrasound that he said don't look good at all. These could be down syndrome, trisomy 13 or 18. We're getting genetic testing done but it'll be a week before we get the results. Has anyone had this happen? I'm under 35 without any risk factors for this. I'm just reeling right now. We have a beautiful 1 year old son. So scared and worried.