Late for a very important date

Hey!! So I am sexually active and pretty paranoid about pregnancy - at this stage we only use a condom, however we are careful. My period can be irregular however whenever my period is late, I have all of the premenstrual symptoms before my period is due to start, sore boobs, cramping, headache, bad skin etc. if I ever were to be pregnant, would I have the period pains and symptoms even if I wasn't going to get my period? Or should I take the warning signs as a sign to relax, that I will eventually have my period?