USED PLAN B

So I had my period already for the month of February. So technically wouldn't start next cycle till the 11th of march. So to get to the point of all this. Me and the BF had sex with a condom but it broke 😔. When we were out after the gym. Went and got plan b(second time taking) Took it no problem, this was a week ago. Today went to the bathroom and was bleeding with lower abdominal pain😢 ! ? Not worried, not panicking. Just curious if this has happened to anyone else?