Implantation bleeding or period??

Car

I would appreciate any help. I started what seems to be my period yesterday, 5 days early then my predicted start date. I have really bad cramps but also missed a day of birth control 2 weeks ago. Thing is that it’s lighter than my usual period and kind of dark brownish/red. Is there any way that this could be implantation bleeding or just breakthrough bleeding from missing?? (Very much hoping I am not pregnant haha)