Today is 23 jan 2010. The lat unprotected sex me and my finace had was 12 jan 2010. I ended my period 13 jan 2010 and 2 days ago I started to spot with this pink vaginal discharge. It's very light but I also have these light cramps in my belly similar to menstral cramps and lower back pain that is killing me. CAN ANYBODY TELL ME WHAT MIGHT BE WRONG?