Progesterone and spotting on 7dpo

I had a stillbirth in March and was cleared to start trying this cycle. My ob put me on baby aspirin and to start oral progesterone on 3 dpo. I'm currently on 7dpo and my bbt dropped below the coverline. I read it would raise my bbt not drop it but when I went to check my Cm there was a very small amount of blood. All day today I've had a high amount of creamy-ish cm until tonight while I was getting ready for bed. Is the progesterone not working? I had implantation bleeding with 2 out of 3 pregnancies but I didn't think you could while on progesterone. Any ideas or similar experiences? I don't see my ob until the 5th which would be 15dpo. This is my first cycle using progesterone like this and not just to jump start af.