8wk scan but measuring 6wk and no heartbeat

Had abdominal and transvaginal ultrasounds today - I'm 8 weeks 2 days according to 1sr day of last period, and my ovulations have always been on time. Yet, today the dating scan out the fetus at 6 weeks and couldn't find a heartbeat. I'm freaking out trying to understand how it could be 2 weeks behind, and the lack of a heartbeat. I haven't had any pain or bleeding. Definitely still symptomatic but mild.

Has anyone had anything similar? I'm trying not to freak out.