Plan b or??

I took plan b on Monday, the condom fell off and he never came in me. I took plan b about 30 minutes after. I was on the 5th day of my period, and my periods usually last 8 days. Today is the 8th day of my period and I’m bleeding way more than usual (the 8th day is usually no blood at all). I feel cramps and my legs are killing me, it feels like I just walked miles on miles. Is this normal? I ovulate in like 2-3 days.