BBT drop 4w3d pregnant - on progesterone- concern?

I got pregnant with 2nd round of IUI this month and had a blood test to confirm at 12dpo with HCG at 115. That was 4 days ago.

I have worn an Oura Ring that has tracked my temps for the last 2 years. Since pregnant, my temp has stayed +0.1 to +0.3. This morning, it was -0.9. That’s a significant drop for me. I’m on progesterone already.

I’m super super worried that this will be a chemical pregnancy. Has anyone had anything similar happen? I’m in a mild panic and scared.

Thanks for any help ladies! I go back to the doc tomorrow for another blood test.