Early scan measuring week behind?

Hey ladies, I’ve had three previous early miscarriages so they wanted me to come into the doctors early. I went in on Monday, which should have been 6 weeks and 2 days. I was told bloodwork was fine. But on the ultrasound they could only see the yolk sac, no fetal pole doctor said i was measuring 5 weeks. And on the opposite side of the yolk sac I had a large pool of blood that the doctor said would have to come out. I went back for bloodwork yesterday (Wednesday) to make sure things were still progressing. I haven’t heard back yet. I have another scan next week. I’m really concerned about the ultrasound and that we couldn’t see much at all. Has anyone experienced this? Any success stories?