So last sunday on the 22 I took a plan b pill, and it's already been a week that I havent gotten my period. And I havent even gotten my period from this month? Is this even normal???

So 1 or 2 months ago I was taking birth control pills and I didnt have unprotected sex until the 1st week and a half of taking the pills... After I just let my bf cum inside me. Last month I got my period and I was spotting a week after I had got my period. Now this month I havent gotten anything. And not only that just today I started to feel a tiny bit of nauseous.