Confused

I'm really confused cuz I had my period but the thing is I was cramping for a week before and when I did start bleeding it was only for two days (I usefully go for 3 heavy then spot on the forth)but this time I only blead for 2 days and it was very light then I spotted a little and it was over barely cramped and the never happens so I'm very confused and just wanted to see what y'all thought thanks