Late AF ❤️

So I came off contraception in October, and since my periods have been absolutely normal, and every 4 weeks without fail! This cycle I haven't been bothered by it and forgot to be honest what with turning 21 etc, I woke up this morning thinking il check when I'm due as I should be by now, I'm LATE! 😳 this will be the most amazing thing ever if I am pregnant, but I'm worried! I drank so much at the weekend celebrating my birthday, would this affect anything if I am? 
I'm petrified to take a test, has anyone else felt like this and can give me some reassuring words? 
I feel I should wait a few more days and see? But don't know if I can? 
I'm adding anonymously because there's ladies on here that know my husband, and I don't want it getting back to him till k know for sure ❤️❤️
Thank you in advance 💕