Scared prayers needed

Tammy
Anyone had to have cvs or Amniocentesis??
Have found out that I have a high risk of having a downs baby and am booked in for this test tomorrow.
I'm so scared of miscarrying or there being something wrong with my baby.
Tried for a year to conceive and want this little person so much I'm so frightened of losing my baby and would be too scared to try again if anything went wrong 
Any ladies can offer advice?? Hubby not too supportive as he's secretly scared too :(