why is my period late? am i pregnant?!

I was supposed to have started on thursday, now it's practically tuesday. i feel like im on my period, seriously, like full blown. like since last tuesday i've been extremely grumpy, which honesty im not always like that on my periods, only the bad ones. also my face has been breaking out and i've been constantly hungry like i usually am on my periods. last night i started cramping so i figured that meant it was coming very soon because i never cramp more than a couple hours before my periods come and i never have any syptoms more than 2 days before i get it so im pretty confused right now. Wednesday though i was extremly stressed oout, like the most that i've probably been in like a year, so i know that could have affected it but i still feel like i should have gotten by now. am i just psyching myself out or whats up?
also, i dont know if this has anything to do with it but i think i may possibly have some kind of infection because i've been having a lot of white/yellow gooyish stuff come out lately on my panty liner and it kinda smells a bit odd. dont really know how to describe it. could that delay my period? help please!!!