I have my nuchal fold scan tomorrow, and I have been reading...?

... so many scary stories about people being given false positives for Downs Syndrome. Has anyone been given reuring results after the scan - and subsequently the blood test around 16 weeks - that have turned out to be ACCURATE? I've had 2 healthy babies already, but I feel so nervous this time around as it's been almost 8 years since I had my 2nd child, and I'm 36 now! Reading about false positives and false negatives is scaring me so much! Thank you!! xx