I would definitely take it easy and not push yourself right now. Maybe even stay off your feet as much as you can. It's a good sign that your levels are increasing, when are you supposed to go back for a checkup or scan?
I think that all miscarriages are called " threatened " if there is just some spotting. I had one when I was about 6.2 weeks along at one day it was called a " threatened miscarriage " and the next it was called an " incomplete abortion ". See your doctor and keep an eye on your bleeding. Even if it is just spotting.