Stressing or pregnant?😶

My period is late by one day. (Yesterday I was suppose to start) I know it's possible I'll start it. But usually it's always on time or a couple days early. I recently started a new job(8/28) so it could just be change of life style, I've been getting up earlier. Last month I started my period 3 days early. Today at work I wiped and this is what was on my tp. I havent had that on my tp for a few hours now. I have the Mirena IUD and it's been really effective while having sex. I just want to know what's going on, if anyone knows???😶😶