Could the plan b not work?

Had unprotected sex with my bf and let me cum inside of me. I’m not on birth control and was in the middle of ovulating when it happened. I took a plan b but not until 2 days later. I had no symptoms from the plan b, no bleeding or cramping. I read somewhere that plan b doesn’t work during ovulation. My period isn’t supposed to come for another week and a half. Thoughts??