2 months ago was last unprotected sex, 2 regular period since, now late period? with pms symptoms. why is my period late?

Can't tell w/o exam: Not all protection methods are 100%, so you can't absolutely rule out pregnancy. PMS symptoms are not unique to pre-menstrual effects and could be part of whatever is delaying your period - ovarian irregularity, for example. It's good that you no longer have unprotected sex. That's a very smart move, but now visit a doctor for an exam and do another smart thing. It'll become part of your style!