Birth Control Cramps

I started taking the combination pill on November 10th, and am now on my last row, second pill, of active pills. However, I woke up this morning with very bad cramps, just like my regular period cramps. I haven't been spotting and it is making me nervous. My doctor told me that I would be protected from pregnancy after a week of taking the pills, so I waited to have sex until after that week. My fiancé and I no longer use condoms, but he came inside of me. I got a bit nervous, I had a surgical abortion on July 2nd, so I bought a test and it came back negative. My questions are: Why am I cramping if it is not my "period" week yet? Could it just be my body adjusting to the hormone? And should I be nervous about him finishing inside of me?