Help. Scared

K

Ok so I’m 14 weeks and 5 days. Today we had a check up and doctor heard baby heart it was around 155🥳 but my doctor wants me to come in Friday so she retest my blood work. Because she told me to say that the test they did for Down syndrome came back 100% positive. She said she think the lab messed up because they already had the wrong dates on my test. I’m super scared this is my second child and I’m 21, this have around been a rough pregnancy ... anybody us went through this and everything was fine?