You are not alone Picky in feeling anxious. I'm 14+2, it's my first and I'm nearly 40, so I've also been feeling nervous about things, since I found out I was pregnant.
I had my 12 week Nuchal Fold scan 2 weeks ago and was convinced the baby would have DS. Fortunately, they tell me the risks for my age turned out very minimal.
I'm the world's biggest worrier and have a tendency to be very negative. I can't wait until my 20 week scan, just so they can confirm baby is still alive (sorry, I'm not being much help here).
I suppose all I can say, is what many people have been saying to me, is to try to remain positive, keep busy and try not to dwell on anything or read too much about what could go wrong. That's my problem, always searching online and finding things I don't want to.
Good luck with your scan.