LFHT 98 BPM 6 Weeks

Adriene

I had my first US yesterday thinking I was 8 weeks 1 day based on ovulation and last day of period . Based on US I am only 6 weeks as of today. FHT 98 beats per minute and my yolk sak appeared abnormal. They want me to come back in 3 weeks for another US and to determine MC or viable fetus. Has anyone experienced something like this? Looking for advice.