Plan B

hey... So just wondering if plan B can make your period late a month after taking it?? I took plan b in June, still got my period on time. This month (July) it's late. I was due for my period on the 18th and today is the 22nd. I have all the classic symptoms of my period coming but it just hasn't started. I've taken preggo tests and urine test they come out negative. Just wondering if anyone else has had a period delayed months following taking the Plan B?? Is it normal?😕 Thanks girls😊