Implantation bleeding?

Madison

This is a picture of this months calendar. I ovulated on the 4th. My husband and I dtd on the 4th and the 2nd. I do not ever spot before I start my period but today I have had light pink spotting, only when I wipe. No cramping. I took a pregnancy test yesterday and it was negative.

Could It be implantation bleeding or is it too close to my period to be? I am two days away from my period.