Period or implantation???

So according to glow, we had sex during ovulation time on the days we suppose too. My period suppose to start on April 16th but on April 9th I got a little nauseated after eating dinner. April 10th I woke up with diarrhea (sorry tmi lol) and my “period came”. At first it felt regular but then by night it was just light spotting. I have not needed a pad. The second day it was only drips of it when I would pee and it was a dark color. This morning it’s only on toilet paper and it’s this color on the pics. One is with and without flash. What do you think?