My boyfriend and I often mess around together, but we've never had sex. The last time I had a regular period was the end of July, and then in August I thought I started my period a few days early, but it went away over night. Now it is the beginning of October, and it never fully came in August or at all in September. I've had PMS symptoms for about 3 weeks now, including tender breasts, abdominal cramps, and mood swings. Like I said, we've NEVER had sex, and he may have fingered me with some *** on his fingers, but we both agreed that it is unlikely for him to have used sticky fingers. At the same time, I started working out and trying to lose weight at the end of summer, and have also been stressed with school... Is there any way that I am pregnant? Or is my suddenly irregular cycle a result from stress and other natural causes?