I just had a normal period on June 17th and it ended around June 21st. My last period was around May 15th and my periods are pretty irregular because I'm very young. Even after my period is over, I have been experincing some symptoms such as nausea and camps. I woke up this morning with terrible cramps in my lower abdomen and the opening of my vagina hurt. I also have occasional heartburn. But I have never had sex before, so there's no way I cold be preggnant, right? Whatis wrong with me?