Need help and advice!!!!!!!

Jazmin • Mother to an angel... I love you Adelyn Rae Bower 5.8.15
So I was told today that my part 1 blood screening for Down syndrome came back negative with a 1:15,000 chance that my baby has DS
But part 2 of the blood screening was for neural tube defects and those test came back irregular with a 1:17 chance of my baby having a neural tube defect like spina bifida. 
I had more blood taken from me today to see if I'm a carrier of any of the genetic disorders and I get the test results back on either Friday or monday and then I have a specialized extra detailed ultrasound on April 16th to confirm if there is anything wrong with the baby. 
My doctor told me that they've had false positives and that there could be nothing wrong with the baby at all but I am just super freaking out about everything and stressing out. Has this happened to anyone in their current or past pegnancies? Please comment with your experiences!!! Please and thank you!!! :(