Bleeding after sex

So I'm panicking a little right now. My last period ended on May 16th. I had unprotected sex on May 22. He pulled out and according to my cycle, I would only have about a 3% chance of pregnancy (still dumb and doesn't mean I can't get pregnant - I know). So I took a plan b pill 2 days later just to be sure. Today - a week later - I started bleeding (light/medium) with very mild cramps. I've been trying to research if this is normal but find myself getting more paranoid by people's posts online. I'm assuming (hoping) this is just ovulation bleeding - since it's about 2 weeks before my next period will start (supposed to start June 15). I think I'm just being paranoid and overthinking all of this. But thought I would post anyway and maybe someone can ease my worries.