Early period!?

Hey guys just after some advice. I ended my last period on the 3rd Dec and on the 20th (nearly 10 days early) I started spotting. It started out really light for 2-3 days and then got bright red and medium flow for 2 days and is now just gone. Has anyone else ever had a period this early? Glow said I ovulated from the 10th and my partner and I BD a few times throughout ovulation time. It was way lighter than a normal period but seems to be too heavy for what everyone describes implantation bleeding to be. Any help would be amazing!