Empty Gestational Sac at 10 Weeks

This is my first pregnancy. I came for the first scan when I was 8 weeks and the doc mentioned that they couldn't detect anything as it was too small. 2 weeks later I came for the scan again, and the doc seemed confident to say that this pregnancy will be failure due to an empty sac with no visible embryo. The gestational sac shape is also abnormal. I bought a cheap doppler to check for any heartbeat, it is relatively on the low side between 70+ to 90+ BPM which is unusual for a 10 weeks fetus. It was very confusing how I could able to detect a little heartbeat but the sonographer/doc are unable to detect any embryo. Does anyone experiencing anything similar to mine?