First Tri Scans

I'm 12 weeks today and had my official first tri scan. My husband came and we were thrilled to see a baby shape (last scan looked like a flickering grain of rice!) and they are so active, twirling and flipping like crazy with a visibly strong heartbeat. But the tech kept measuring what looked (to me) like excessive fluid behind the neck, and then measured another spot away from the baby a ton. She would not comment on the measurements and did not print a picture for us. She threw a towel at me to "clean up" and said she had to get the dr. Then she verified my age, twice, which is 33. A few min later she returned to say that the dr had left for the day and she had made an apt for me to come in Mon. She said due to the baby's position she couldn't get accurate measurements and would need another scan when the dr is in. When I expressed concern about the scan and said I had a presentation at work Mon so would another day work she emphatically stated I must come in ASAP, and should come in Mon. I'm really scared. I have no idea what could be wrong, but I'm scared the tech thinks downs? this is my first pregnancy. I was so excited for today and was going to announce this weekend. Now I don't know what to do.