Implantation bleeding???

My period is supposed to start either today 6/1 or 6/2( some apps say differently). Went to the bathroom and wiped 8am and got light pink. During the day got nothing else till 4pm and got the same thing. Only when I wipe, and just when I wipe once. Very mild pelvic pain but it's on the sides. I hear implantation bleeding sometimes can happen even after your expected period. What do you think this is?