Plan B- help

So my boyfriend and I had sex (with a condom but it fell off mid-sex before he came) and we immediately stopped once we figured the condom came off. I took plan b that same day and had my period the week after. The only thing is that my period that I had the week after was two weeks early compared to my normal cycle. My question is.... will this period be my new cycle or will I go back to my normal cycle?