I'm 17 and my period is about 9 days late. I've been experiencing period like symptoms the past week but nothing has happened, tender breasts, occasional and slight abdominal cramping. I had protected sex 2 weeks ago and I'm worried I might be pregnant. My exercise regime has increased dramatically the past 3 weeks and I have been stressing over separate issues as well, so maybe it's due to stress? I don't know but I'm worried!