I dont know what to think. My period is always on time and so is my ovulation. Me and my bf had sex on 8/12 and he went inside me. The 12th also was the start of my fertile week. And my ovulation day was on the 17th. I can ALWAYS tell when I ovulate because I get the worst cramps the day of. But this time I couldn't feel when I ovulated and I'm supposed to start my period on the 31st. And this week all week long I've had the worst cramps and been really tired to the point when I come in from work I lay down and take a nap. Anyone else experienced anything like this before? Is it a possibility I could be pregnant?