I just read your comment about being on your period for an entire month with taking the first pack of BCPs. Is this something you experienced? I have never experienced this with my BCP (I am not taking Yaz, is this a common side effect of Yaz?).
From what I understand, starting a new birth control pill (BCP), or even missing a few days of taking the pill, can cause some spotting (lighter flow for a few days), but not similar to having a period (heavier flow) for a month.
I would think that any woman experiencing this should talk to their doctor who prescribed the BCP to discuss this.