WHY WAS MY PERIOD ALMOST 4 DAYS LATE AND ITS REALLY LIGHT.

I WILL LIKE TO KNOW WHY MY PERIOD WAS ALMOST 4 DAYS LATE AND MY PERIOD IS VERY LIGHT...I ONLY BLEED WHEN I GO TO THE RESTROOM AND IS A LIGHT PINK COLOR....BUT NOT MOST OF THE TIME...SOMETIMES I JUST URINE AND NO BLOOD...PLEASE SOMEONE HELP....CAN I BE PREGNANT OR AM I SICK... IM REALLY WORRIED...I HAD BOUGHT A PREGNANCY TEST BUT I DIDNT WANT TO TAKE IT BECAUSE I THOUGHT MY PERIOD HAD CAME BUT IM NOT BLEEDING LIKE MY REGULAR PERIOD...PLEASE SOMEONE GIVE AN ADVICE AND HELP