little bit of help please!

okay so,im 15. Earlier this month,i went to a party.And i got a little bit drunk to say the least (oops😶)my period is late and i know its probably just that but i am quite scared theres a chance i could be pregnant. I was extremely drunk at the party and i cant remember anything. I asked my friend who took care of me that night and stayed with me the whole night (it was his party and he doesnt drink) and i stayed at his house the night. He reassured me nothing happened however someone said i did have sex. I'm really worried,does anyone have advice?thankyou ❤️