Period or implantation bleeding???

AngO

My husband and I had sex April 1st which was also the last day of my ovulation. Yesterday, April 10th I started a light bleeding that has rolled over into today. It’s not heavy, don’t have to wear a pad.. only see it when I wipe. Been extra tired the last week, headache and back pains.. and had diarrhea today. My period isn’t due until the 15th... not sure what’s going on! Any advice or input is appreciated!