Last Tuesday (August 23), my boyfriend and I were dry humping (I was completely naked, but he had his briefs on). He may have pre-ejaculated, but he said his head never actually touched my vagina through the briefs. I was wet, so I'm really worried that some sperm could have gone into my vagina. (My hymen is still intact, by the way.) Today is Saturday, August 27. I'm supposed to get my period around this time of the month, but sometimes it's late because of stress and exercise. Could I be pregnant?