Worried prenatal NT screen results?

My results came back 1:690 the numbers for a 30 yr. woman im 19. I'm so beyond worried !!! Doctors aren't concerned and neither was the genetic counselor I spoke to. My doctor was sweet enough to not give me my results without referring me to a genetic counselor first. If she would've just gave me the papers I would've been freaking out! It's a negative result and I had an early anatomy scan right after my counseling  and everything came back normal looks normal but baby supposedly measured a little small? Nothing major but I'm so worried !!!! She was measuring normal at 14 weeks.