Implantation bleeding or period

My last period was on January 25 and I had unprotected sex(I already know it’s done don’t say none💀) on February 5 and then my period was predicted to come on the February 16 but it came on the 18....I had really bad cramps and i bleed for about 7 days but my period was lighter...was it implantation blood or period blood, it was enough blood to cover up a pad, I had to change it a few times and there was bright red blood whenever I whipped...does it should like implantation or period bleeding