Umbilical cord not enough blood??

So I'm 36 weeks and I had a check up today and the tech noticed that the umbilical cord wasn't getting enough blood and he strongly recommended us to get the harmony test for Down syndrome because that was usually the case! Now I'm just worried because Dr google scared me and on top of this I found out my cervix is measured at 2.3cm. So what does that mean will I not carry FT? Help I'm a first time mom and I'm just really scared, my husband is the best support ever but I just need some other opinions!