Implantation bleeding?

Today is the day after my ovulation ended, and I had a little bit of blood in my cervical mucus. I'm worried that it may be implantation bleeding.

Last Saturday night, I had protected sex with a condom, and I finished him off with a blowjob afterwards, so I know he didn't come in me at all, but I'm worried that I could've gotten pregnant from precum.

What do y'all think?