Miscarriage / stopping progesterone

We found out today that my pregnancy is no longer viable. My doctor had me on Progesterone 200 mg twice daily. He told me to discontinue the progesterone. My hcg level way 167 last Friday and 300 today. We also had an ultrasound today and there was nothing there, just a really thick lining. I go back on Monday to have my levels checked again and another ultrasound. Does anyone have any insight on this? I’ve had two miscarriages in the past but didn’t know if I should expect anything different..