Bleeding a week after period ended

My period ended on the 26th of October after going on for 9 days. I’m normally like 6 days on, the first 3 can be heavy then go light. This time it seemed lighter (still heavyish tho) but took longer to go. Then around Monday I’m thinking I’m cramping like my period is gonna come, you just know when your about to bleed by the specific pain! So anyway it came as very light pink then went brown quickly, now it’s been about 2 days of a mid flow, like a period basically. I’m cramping quite a bit and I think my body is exhausted as I’ve just finished the last one. I’ve recently switched to working nightshift within the past 3 weeks instead of day shifts so I’m not getting to sleep until after 5am and then sleeping till about 1pm so my body clock has changed, is this a possibility that the change could have caused this?