Implantation bleeding or "period"? Can someone please comment

Samantha
How do I know if it's my "period" or implantation bleeding? Tomorrow I take my last pill of my pack (21 day pack) and since yesterday I have been spotting, started light with mild cramps, and today a little more, it was in my underwear, and when I wiped. What is this? And it sorta started like this last month, this is my second month taking bc.