HCG good or miscarry?

Hello!

I had a miscarriage back in may/jun of my first pregnancy and didn’t find out until I was at my 8w ultrasound. Found out I was pregnancy early august, last period was 7/11 so I should be 5/6 weeks right now, and wanted to do some testing to make sure I wasn’t miscarrying again. The nurse said it should double every 48 hours, it barely doubled at all, is this a sign I’m miscarrying again? I haven’t have a chance to talk to a doctor, because they’re closed. Im going to call tomorrow but I’m panicking now.