Symptoms of pregnancy but no BFP

I am having unusual symptoms and am due for my period in 7 days. I got my period on the 17th of Nov. and finished on the 20th. My cycle is generally short, around 24-25 days. We had unprotected sex during my period (gross I know) and the day after it. Every month (consistently), almost two weeks before my period I have EXTREMELY tender breasts and cramping that generally goes down into my legs as well. Have always had those PMS symptoms pretty bad. I noticed I have none of those symptoms at all and its 7 days until my period is supposed to come. I ALWAYS have these symptoms a week and a half to two weeks before my period which is why its strange to me. I noticed my temp is also slightly elevated (99.2-99.3). I have been feeling nauseous after almost every meal as well and sometimes even lack of appetite due to it. I took a test today but it was negative. I just cant really ignore the fact that these symptoms are so unusual for me. I check my temp fairly regularly and its never elevated. I've never been pregnant. I read its not a good chance to get pregnant during the times I had sex, but the symptoms are unusual for me.