Found out I may be having a down syndrome baby!!!

Went for an high risk scan today because about 3 weeks ago I had one that revealed I'm having a girl and other issues....so today my doctor looked at my scan pics and saw some concerns....first she said the walls around her heart is kinda thick this could come from me possibly having g diabetes so she want to monitor that...second the doc said she was measuring kinda small......I have small babies both of my babies weighed 6 pounds and some ounces can't quite remember at birth.....third she said she do not see a nose bone growing for which cause concern for the down syndrome.... She said there's a chance that she could have it but sometimes just because there isn't a nose bone dose not mean that she would have it....so they took so blood samples from me and I have to go back in a couple weeks to get results.......even though this don't bother me much because I'm still gonna love my baby girl regardless it just make me think like what could I have done wrong for her to have down syndrome??? I take my vitamins..and eat pretty healthy when I'm not craving crazy things....anyone else experience this???