Plan B/ Late period

EMERGENCY! Ok guys so I had protected sex 4/03 but took plan B just to be sure because it was our first time, for both of us. My last period was around the lates 20’s of March, my period being irregular usually comes 3-4days earlier then the pervious month so i was expecting it in the early 20’s of April!! BUT YALL I HAVE NOT GOTTEN IT YET! I took 2 pregnancy test this last weekend and they came out negative 😩 I don’t know whats going on ladies please help me!?!

*update* ok yes I know Plan B is only meant to be taken for when you’ve had unprotected sex. Since it was our first time we wanted to take extra percussion. Yes, I was expecting it to delay it for a week or so but it’s been like 2 weeks now which is why I’m worried