bleeding after Plan B

So I was having sex and the condom broke so we took plan b maybe a little under 48 hours. I had my period just before we did it and now I'm getting it now maybe a week after. It's not extremely heavy but it's borderline and I'm wondering if this means it's working. And also how long you think it would last? Anyone's opinion or story I don't care I'm just nervous that it's not working or something.