HCG concerns

Okay I am kind of freaking out here. I had an ultrasound and blood work done yesterday, I should be 6 weeks 6 days, but baby is measuring a day behind (6weeks 5 days) with a heart rate of 133. And on top of that my HCG didn’t double, It went from 33,851 (3:49pm) to only 53,328.2 (12:18 pm)