Possible implantation bleeding?! Please help!!

On the 20th and 23rd of May, my boyfriend and I had sex. We used a condom both times, and I’m pretty sure he pulled out as well, but he might’ve not been telling the truth when I asked. I was having no early signs of pregnancy, but yesterday he came over and ended up fingering me. We noticed a really small amount of pinkish/reddish blood on his fingers. Could this be implantation bleeding or did he just scratch something?? It’s now 2 days after the bleeding and there is no more trace of it. It seemed to have ended that night. After we noticed it on his fingers it turned into a light brown color. There wasn’t a lot AT ALL not even enough to fill a single tampon. Could this possibly mean that It was implantation bleeding??