I've Taken Primolut To Delay My Period , I've Stopped

I've taken primolut to delay my period , I've stopped taking it on Saturday. I still haven't received my period but I had unprotected sex on Sunday and going my my menstrual chart I was highly fertile.
My question is should I go and get the morning after pill to be safe or will I be fine once I get my period which I'm estimating should be in the next day or too