One baby in tube, one in uterus?

Looking for some insight. This has been a horrible experience and I'd just like to know if anyone has any thoughts or similar experiences. 

I found out that I was pregnant oct. 18th- 5 days before my period, but I was having such strong symptoms that I took a test. It is a high risk pregnancy so my OB had me come in early and do an ultrasound to see if maybe my last very light/short period wasn't a period and i was actually farther along. The ultrasound only showed a tiny spec that she thought would be the sac, and she thought i was 4 weeks instead of 5. They started me on betas and they were 1,072 --> 72 hours until the next one and it was 2,300. then 48 hrs - 3,941. Since it was a slow rise the OB said to do another ultrasound in two days. So it was just a week from the first one. They saw the sac had grown a lot for sure, but no baby. She also noted that they was a lot of fluid around my left ovary and asked me if I was having pain over there. 5 days later I had my high risk consult for getting started on Lovenox. I told them that we hadn't seen a heartbeat yet and I'd like confirmation before starting the injections. They did an ultrasound and it looked exactly the same. Sac, no baby. They told me that I would probably be miscarrying soon and I could go home and wait. They took my blood before I left and said they'd expect my levels to be falling. They called back the next morning and said my hcg had risen to 12,790! So they wanted to see me in another week for another scan.

That was today. She started on my stomach despite my protests, and saw the sac again which looked larger, and possibly a little blip of something with the faintest flicker behind it. It was so blurry and grainy though and she couldn't even measure the heartbeat- if that's what it was. There wasn't even a distinct shape of a baby. She tried again transvaginally but it looked the same. Then she spent a ton of time looking at my left ovary in silence. The doctor came in and said they might have seen the heartbeat but it was hard to tell, and they thought that there might also be a second baby in my left tube. She could give me no answers and just said they'd take my blood again, have a specialist review the pictures and call me later today. I have heard nothing from them so far but I am grasping at straws for answers.