Period or implantation???

So i got what i think was my period saturday night/sunday morning. It was just like spotting. Sunday i had a light flow and now today (monday) my "period" has been on and off all day. I did have some cramps on sunday but they were not as bad as i usally get them. Just wondering because my normal period is suprr heavy with bad cramps the first two days and then usually medium/light rest of week. Any ideas would be appreciated!