Beginning of period?

I have unprotected sex regularly with my fiancé. However, we track my cycle and use that as our form of birth control, mostly bc we are not actively trying for a baby but would not be upset if we were to have one. I normally cramp for a week or so before my period is due, and I didnt this month. My period was due yesterday, and I spotted this little bit, but no more yesterday or today and still no cramping. I have a 36 day cycle so I’m not sure if it would even be possible for me to have implantation bleeding on the day my period was due. Normally my period comes on all at once and very heavy. I’ve only had one other period in my life that I remember spotting but it was more frequent and I cramped really bad leading up to it. I guess what I’m trying to ask is, what are the chances this could be implantation bleeding? I mostly just don’t want to get my hopes up and go off buying tests plus if it’s implantation bleeding I’m sure it would be too early to test 🤷🏻‍♀️

I should also add that today I had a good bit of clear discharge.