Implantation or Period spotting

I am suppose to start my period Jan 9th ( 3 days) yesterday and today I noticed when I wipe it looks like picture shown. I don’t want to be pregnant. I just want to know if this is implantation or my uterus shedding ? I had sex Dec 22nd, Dec 25th. No ejaculation was done at all. I’m just nervous and don’t want to be pregnant. I have no symptoms , besides cramps which is normal the week of my period, and feeling like I have to poop. No sore boobs, only 1 sore nipple bc it got injured . Lol. No peeing, Not fatigued. Nothing.. I know I need to take a test but I’m just trying to see what this is .