late period

So my period is now 4 days late. Me and my boyfriend have been very sexually active with no form of Bc (I know. So stupid!) my period is not always on time. The fact that makes me nervous is I've had no normal symptoms I get before I get my period. I've been tired lately which could be due to work and the stress of my dad dying. Though my breast are also very tender, not just my nipple but the whole thing. Idk if I'm over reacting or if I should take a Pt. Is my late period normal? 
update- I took a pt test and it was negative!