BCP? Pregnant?

I had a miscarriage Nov 14. I immeadiately went on Yaz and had breakthrough bleeding for two months off and on. I stopped them for a month and then started Yasmin. I had breakthrough bleeding the first month and only had two days of bleeding on the placebo pills. I haven't had a normal period since my miscarriage. Now I'm starting the second month and I'm having headaches, tons of white milky cm, and my seem tender? My fiance and I have regularly. Is this effects of the birth control or could I be pregnant again? I plan on taking a test tomorrow just to be on the safe side.