2 weeks late on period! 17 and irregular.?

Posted: 29 Mar 2015 05:09 PM PDT

first of all i did not had sex since last period and ive never did unprotected sex. im always irregular, experience common pms symptoms like headache etc., but my breast are completely normal, they are sore or tender a week or so before my period shows up, but now they are normal. am i pregnant? does absence of some pms normal? what are the odds that im pregnant? please help