First ultrasound - no embryo

I had my first transvaginal ultrasound today at 8+2.

The ultrasound showed a gestational sac measuring 17.3 mm, but no yolk sac or embryo. They said to be certain they will schedule another for March 17.

They didn’t tell me how many weeks I was measuring, but Dr. Google says a gestational sac measuring 17.3 mm could be anywhere from 5-6 weeks.

I’m feeling so devastated, I know the odds are not very good that this pregnancy will progress. Anyone else had a similar experience?