5 weeks 3 days...help!

Went for my first early ultrasound as I had an early MC a few months back..according to my LMP I was supposed to be 6weeks 2 days but I ovulated late and I’m measuring 5 weeks 3 days. We only saw a gestational sac...the ultrasound tech/ and midwife sounded as if we should have seen more and now I’m extremely anxious...is this normal for this early?