Abnormal 1st trimester screening

I'm currently 13w 2days and had my 1st trimester screening a week ago. The fluid behind baby's neck was 1.5, well below the "abnormal" range and they were able to see the nasal bone. Ultrasound tech said baby was developing perfectly and it was moving around like crazy and the HB was 162. I received the blood test results a couple days later and they showed risk of trisomy 13 & 18 and my doctor suggested I have the Harmony test done to test further. This is my first child and I'm so terrified of what the results will be. Has anyone else been through this and could you share your experience? Thanks so much!