Implantation bleeding?

Hi all, so yesterday was CD28 of what is usually a 28-31 day cycle (not sure exactly when I ovulated) and I used a finger to feel my cervical position, and when I removed it there was brown spotting/discharge. I assumed it was my period starting and put in a lite tampon. This morning I removed it and there was barely any brown on it, and I haven't had any other spotting or signs of my period today. I have never had brown spotting BEFORE my period, so I guess I am curious if this sounds like implantation spotting? I took a frer (albeit on highly diluted urine) on CD26 and it was negative. Does anyone regularly get brown spotting a day or two before their period, then nothing, then their period? Thanks.