Blighted Ovum????

Long story short.. Based on LMP I am 7w3d. Couldn't see anything today. Looked like an empty sac BUT I go back in two weeks to check again bc I am still really early, hcg is 20,240 and I repeat labs in 48 hours. If its going up it could still be good news. I have a tilted uterus which can make it hard to see. That # puts me at 5-6 weeks which if so means I found out literally as soon as I was pregnant. She said just a week or so ago they thought a lady had a blighted ovum (sac and no baby) but ended up finding it a week or so later and the HB was strong. So we haven't lost hope, just gotta wait it out. Tech saw a small bleed above the sac but the Dr. said it still doesn't count me out. Progesterone was 10.9 but she said its still normal and didn't want to put me on a supplement. Thoughts??? Experiences???