Fluctuating Progesterone?

Katie

Wondering if anyone has had a similar experience. I went in for an ultrasound at 6w1d. All they saw was a gestational sac and a yolk sac - Doctor and I both guessing I’m early as I believe I ovulated later in my cycle.

She sent me for bloodwork twice to check my levels. My hcg rose appropriately. It went from 17,540 to 29,720. However, my progesterone went from 19 to 12.99.

My doctor said she’s not really concerned with that because progesterone is an “old school way” of testing pregnancy viability???

Wondering if anyone has experienced something similar? And all was well?