Period acting up

On April I got my period for my regular 3 days but is was not the same I usually get it normal but last month i did not even have to use a pad and i did not have blood on my pee I only had light pinksh red blood wen I would wipe that happen for the 3 days of my period but this month I have not gotten my period in my calendar say I was to start on the 6 this month and nothing yet I took a pregnancy test on the 6 the day of my period but it was negative any advice that I can get