I have been on the same birth control for about 7 months now. After my last period, I didn't get my pill refilled until about 3 weeks later. I had unprotected sex while I was off my birth control. I have been back on my pill for about a week and I have been spotting the whole time. It does not feel like a normal period, though. I am sick to my stomach and I feel like my insides hurt. What could this mean?