confused

i started prometrium 2 dpo doctors orders being that my progesterone was too low to carry so we’ve decided to try this for this month, i’m due for AF on monday .. today is thursday and i have NO pms symptoms and no pregnancy symptoms apart from mild cramping in my vagina , slight sharp cramping pain in my stomach and bloating all of these are very mild though. does prometrium stop PMS symptoms? i’m just nervous, really want that BFP! third month trying to conceive but first month with barely any symptoms, any thoughts ? please anything any inputs?