Delay or not coming?

Erien • Just married on March2014. Expecting a baby on Jan2015 :)
I just wanna ask. What kind of stress can delay our period since I am 8days late. I dont know whats happening with my body. Am i pregnant or just my period not regular like before. I took HPT yesterday and got BFN! I thing i am not goin to take test anymore till I missed my period two weeks.