I did mine with ravgen and haven’t received my results back yet but have followed so many women’s stories and DDC is legit. Don’t be stressed. You picked a great company. Your results are accurate. In fact, DDC is now saying their prenatal is as accurate as their postnatal so you have nothing to worry about.
Jojo, please pay attention to dates on the "many reviews" you read. As Rockyroad indicates, the success rate on prenatal DNA testing has been a moving (and improving) set of numbers in the last decade. Don't mix people's remarks from years ago with reviews from this year. Try to be calm, your test is going to be valid. Don't let your fears run the show.