High chance I could be pregnant?

We used a condom, but there was so much friction that before he could put his dick in, the condom broke. It broke very close to my hole/vaginal opening, but he wasn’t inside of me yet. I know I sound silly, but my period is a few days late so I can’t think of anything else besides it could be the Plan B I took a month before this incident and bled. The Plan B was before this incident happened, so I’m not sure how common it is for the pill to effect me for this long. So basically I got my period after the Plan B, then this incident happened, and now I’ve missed my period by a few days.