Period talk need advice

I been getting my period every month now so on March 23 I was suppose to get my period my I didn't..I got it April 2,2017 which I always get cramps at least 3 or 2 days before I start my period but this time I got cramps on the same day and than I started my period..I felt so tired and lazy with this period.My period is light not heavy I don't need to use a pad,only when I have the urge to pee my period comes down.Today is my last day and been feeling slightly cramps which this never happens to me at all.. Is this normal what could this be... any advice or opinions is welcome thanks