Period or implantation bleeding?

Kristina • 3 early miscarriages. 1 stillborn to a baby boy in, momma to a baby girl & ttc ❤️
This is so weird. My period was suppose to come September 27th but I got a surprise early. September 15th I got what I thought was my period which is really weird to come that early. It only lasted a day and a half. It was heavy enough to use a tampon. Would this be my period or implantation bleeding?