please help me

So i have heard that it’s IMPOSSIBLE ago grt prego unless you have legit sex. i didn’t have sex. i never have. but i did mess around with this boy for the first time and we did everything but that. we did stuff feb 11 and my period was feb 1. my period is irregular and track did start so i have been working out like crazy! my period is 6 days late. is there any chance i could pregnant or should i not worry?