Implantation bleeding?

Today I’m 8dpo, had sex on July 24th which was my peak ovulation day. The condom broke and I took plan b about 13

hours later. The last few days I’ve been having mild cramps like I’m about to start my period but nothing shows up. (not as bad as period cramps). I’ve been extremely tired and no energy, lower back pain, constipated yesterday and today. Today I had a sharp/pulling pain on my lower right side, went to the bathroom and there was a light pink discharge when I wiped. I’ve also read online that if you take plan b after you’ve already ovulated then it is less effective or not effective at all. My period is due on August 6th. Just wondering if anyone has had the same experience and ended up getting pregnant. Thanks.