What do you think?

I began lightly spotting (brown) at the time my period was due. I know it could be implantation bleeding, and I will take a pregnancy test in a few days, but what else could this be? I have my usual signs indicating my period is near: slight cramping and sore boobs.

Has anyone experienced this without being pregnant? I'm not necessarily TTC, but the anticipation is killing me! Lol. Just looking to see other people's experiences. Thank you!🤗