pregnant?

so i’m 17 and i have been having sex for about 2 years. my boyfriend and i do it safely and responsibly, but last time we were having sex, the condom broke but he took it out as soon as it happened and continued with a new condom. my period is late by 6 days, though i am never regular with it anyways, but i was wondering if this could mean any chance of pregnancy? i have irregular periods so if that never happened i probably wouldn’t be thinking twice, but i’m very nervous. any help?