Trying not to stress but I'm confused.

Amber
My Af is supposed to be due today 7/11 from when I believe i ovulated. But no af yet- what I am having looks to be or may possibly be implantation bleeding. It's very very light brown not even every time I wipe just a few times. Is this a slow onset to my af? Or did I ovulated later than I thought maybe just maybe this could be implantation bleeding. What do yall think?