Can you have a suspected miscarriage but still be pregnant?

Hi, this is probably all very silly but I had a miscarriage in december at 6weeks 4days pregnant. On my notes and during the scan the lady didn't sound too sure and kept saying "well it appears you have but can't be sure etc" she also showed me a very visible blob on the screen and said it was broken down tissue which would come away by itself. As I wasn't far I was shocked to how big this already broken down bit looked as I would expect the actual whole baby to be about that size judging from 6/7 week pictures I've seen. In fairness she did tell me to do a test 2 weeks after which I haven't done. Anyway, I haven't had a period more than 11 weeks on, over the past 2 weeks all I've done is throw up and have had to have time off work because of it, and as weird as this sounds I have been getting heartburn which I have never ever experienced before. Is all this just coincidence or could there be something more to it? :s thankyou x