Today its october 9th, the last time I had my period was sept 19-23 I'm usually regular. The I had unprotected sex multiple times the week after with my partner. Oct 3-5 I noticed that several times (not everytime) I wiped there was some light pink blood in my disharge, but it slowed to a stop. Now I'm having lower back pain and stomach pain that remind me of my period, its on and off. Yesterday there was no cramps, today there are. I had sex yesterday and it was slightly painful and he couldn't go in all the way. My period is suppsed to come either this week or the next. Is there any possibilty that I am pregnant, or is this something else entirely?