Help! Progesterone dropping

Je

I’m 6w3d. I saw a strong heartbeat on ultrasound 2 days ago. My progesterone over the last 3 weeks has gone from 22 to 20 to now 16. I’ve had 3 prior miscarriages. Am I doomed? I’ve been on progesterone suppositories and starting oil injections tonight. Thanks ♥️ and please be honest, no need to sugar coat.