Late period???

Ok so im due my period today, and i knew it was coming, it always comes the sunday after i stop taking my pill for my 7 day break (thursday) and im quite regular, i usually come on in the morning/afternoon but its a no-show at the moment (11:58pm now). HOWEVER, i did have sex around midday, would this in any way delay my period? Im not that worried im just curious :)