cycle days and getting pregnant if past ovulating window

Hey ladies .... 
I'm a regular 28 day cycle . 
I had unprotected sex on the 26&27 day and he most certainly did finish in me . 
Is it just a myth you can only get pregnant in ur fertile window ? 
My question is no matter when you are in your cycle can you get pregnant or does it does it have to be in your fertile window ? 
We arnt preventing getting pregnant