Wacko period!

Ok so ladies, my period was twelve days late and it started finally on Wednesday night. Well the next day's it was super heavy and the day after it was super light and that night it stopped. Saturday I woke up to pain in my lower back and sides and it lasted all day and all the next day. I bled a little bit once on Saturday and Sunday but that was it. Today I have a little pain but it's not near as bad. Has anyone else ever been through something like this?