Thanks for your replies.
The scan does show a nasal bone, which she said is a good sign. The only bloods that I have given so far are those taken on my initial midwife appointment to test for rubella etc. Apparently you can't test for downs by blood until you are 16 weeks pregnant, so I'll have to wait 5 weeks.
They've not mentioned any risk factor yet, I'm guessing that will be next weeks appointment.
I kind of wish I never knew anything.
They panic me with my first daughter, but she's healthy, so I am trying be positive.