Measuring small???!?

I’m supposed to be 7 weeks 5 days today according to my missed period. I had my first ultrasound today, and baby is measuring 6 weeks 1 day. But heart rate at 102 bpm...

is this bad? Idk what to think. Last time I was pregnant I was 8 weeks and baby measured 5 weeks 6 days with no heart beat and I miscarried later that week.

What do you guys think? Should i be worried??

I’m so scared :(