I'm very sorry to hear all the ladies having bad news. 
MrsK I think you might be having some unnecessary worry. I went through similar in my last pregnancy. I had a scan at 6 + 0 which showed a sac, nothing else. I was told I was no more than 5 weeks pregnant, which I knew was completely wrong, or I'd got a positive test at 3DPO! I went back the next day to a different EPAU, and got another scan. At that scan there was a fetal pole and a heartbeat!
I went on to have a successful pregnancy. :)
From what it sounds like, you are under 6 weeks. I know it is difficult, but I think it is just too early on scan yet.