Implantation Bleeding

As of today, my period is about 5 or 6 days late (I’m on CD 37). I’m thinking I may have ovulated late though because yesterday, I had a veryyy small amount of brown blood after peeing, but no bleeding or spotting since. I keep getting negative tests (or possibly very VERY faint positives, if you look at my last post) but if what I experienced yesterday was actually implantation bleeding, maybe it’s too soon for a test to pick up any hCG? Has anyone had a similar experience with late ovulation? Does that sound like implantation bleeding? I’m a little confused but hoping for the best!