I've always bled right through the progesterone, too.

Fri was day 1

I love how doctors/nurses tell you that you won't bleed through progesterone. Yes, that was your period. Progesterone delays your period, it does not prevent it from coming.
My first 2 IUI'S I stopped taking progesterone on D13 because I wasn't pregnant...both times I got my period 2 days later. My third IUI I started bleeding thought the progesterone on D12.
My doctor tells me to continue to the progesterone until I bleed or stop taking it on D14 if I have a BFN.

I know this may seem like a silly question but I am confused about my last cycle. I was on Femara for the first time and used progesterone supplements after ovulation because I have a really short luteal phase. My RE told me to test yesterday (Sat) which would have been 14dpo. On Friday I started bleeding like a normal period, even though the nurse told me I wouldn't get my period on progesterone until I stopped and to keep taking it. Friday night the bleeding stopped and I tested yesterday AM but it was BFN. So I stopped the progesterone and woke up this AM (Sun) to more bleeding which I assume is my period.

So, was CD1 Friday even though I was still on progesterone? Or is it today, Sunday?

Has this happened to anyone else?