5w5d empty gestational sac

Hoping to hear stories (good or bad outcomes) of similar situations. Went to the doctor on Wednesday and got an early scan due to my history of miscarriage. According to LMP I was 5w5d, and I’m sure of my dates because I was using OPKs and I got my BFP at 9DPO. At most my O date could have been off by 1 day. My HCG the day of the ultrasound was 20,000 and all they could find was a gestational sac, no yolk sac or fetal pole. They didn’t tell me how far along the sac was measuring. I know 5-6 weeks is a gray area for what can be seen on ultrasound but I would have thought there would have been more than just a sac with HCG that high. OB just says it’s too soon to predict the outcome and I have to wait for my follow up scan.