Can your period even start while you’re on Prometrium? (Progesterone) IM SO CONFUSED

I’m on CD 10 of my 3rd cycle of Clomid 50mg. I had an OB apt today & he bumped me to 100mg for the next two cycles, followed by 150 the cycle after that. If not PG in 3 cycles, I will probably meet with an RE and/or try letrozole.

During my apt I asked about adding progesterone suppositories, for 2 reasons: 1) I have a bicornuate uterus & a history of stillbirth - supposedly progesterone throughout pregnancy can sometimes help avoid the preterm labor risk, and also because 2) I had a chemical pregnancy my 1st round of Clomid so I’m hoping adding the progesterone could help sustain an early pregnancy.

The dr agreed with both, and prescribed prometrium saying I’d use it from after I ovulate (bbt rise) until AF came or I was pregnant. If I’m pregnant I use it until 36 weeks or until progesterone shots become necessary.

Here’s my question: I’m 10dpo so I was thinking of using it the rest of this cycle until AF comes or I get a BFP, but I don’t really understand if you stop it around when your cycle would be over or keep taking it until AF shows.

BUT, will AF even come while you’re taking progesterone? Doesn’t progesterone have to drop to get AF? Or will AF come anyway if it’s going to come since this is supplemented progesterone? I’m so confused on this. I feel like if you stop taking progesterone to see if it comes it will trigger it to come, so that’s not going to help if you actually are pregnant - you’ll be asking it to fail and going against the idea of supplementing progesterone during pregnancy.

The dr just said days 14-28 (rough estimate based on how long my cycle usually is.)

Should I stay on the meds and AF will just break through if it’s going to come?!