Progesterone dropping

Stephanie • Married 2 years, 4 baby losses. Jun 2017, chemical. Dec 2017, missed miscarriage. Jul 2018, ectopic, lost left tube. Nov 2018, missed miscarriage.

I saw the heartbeat today for the first time in all my pregnancies at 6 weeks, but afterwards, I got a call from the dr office saying my progesterone dropped from 28 last Sat to 20 today. I’m already on prometrium so it’s scaring me. The nurse wants me to start taking it vaginally now instead of orally for better absorption. Anyone gone through a similar situation??