We had a similar thing (except bleeding) with ds3.. my HCG levels were really really high so they went me for an US. A week later we had it done. It showed one empty sac and one sac with our son in it..

I didn't get any bleeding though. They said they weren't sure what the 2nd sac was.. then our GP said it was most likely a twin that didn't develop beyond cells

Sorry for your loss Alexis