Blighted Ovum? Please help me out!

So since I've had a miscarriage before my Dr had me come in at 6 weeks (actually 5w6d). All that could be seen on the ultrasound was an empty gestational sac and a small hematoma and I was measuring about 5w1d. My doctor acted like it was normal for that early to only be able to see the sac. 4 days later I started bleeding pretty bad and I thought it was all over. They next day I went to see my Dr and she did an ultrasound and the hematoma had grown and she said that's what was causing my bleeding. The gest. sac was still in there but she still couldn't see anything inside, although to me the ultrasound was not very clear. She had me do blood tests but told me I was most likely miscarrying. My blood tests showed my hcg and progesterone were still good so she put me on progesterone and told me to keep my ultrasound appointment for 4 days later. I went to my ultrasound appointment and the hematoma had gotten a lot smaller and the ultrasound tech was still trying to see if she could see anything in the sac when the Dr came in the room and looked over her shoulder. The ultrasound tech was looking at a certain place in the sac where it looked like there maybe could be something and she said "I'm not sure if I'm seeing the yolk sac yet" My Dr said " Nope she was in here 10 days ago so we should be seeing something by now." The tech left and the Dr. started telling me my miscarriage options. At this point I was 7 weeks 1 day. They didn't tell me what the sac measured but it definitely looked bigger to me. So now I'm just waiting to miscarry or if I don't soon, get a D&C.; My question is if it is for sure a blighted ovum or if baby could still be hiding and show up in another week or 2?