Why does my period cycle seem backwards

So this is my first time posting here. Hopefully I can get some insight before heading to the doc. My periods have been off schedule, I have spotting for almost a week before starting and sometimes it’s dark and brown. This is something that typically happens at the end of the period. I have my period and then it’s a couple of days of spotting then dark blood and then it’s over. This has been going on for months, it’s weird. Anyone else having this issue and know why? It’s weird.