Helppppp weird period


2 days late. It finally came, the first day was light, 2nd day was medium/kinda heavy. 3rd day shouldn’t have even been considered a full day. I had a couple spots on my tampon. I woke up this morning took a test (my sister told me to just to make sure) came back negative and when I peed a little blood came out when I wiped nothing.

Any thoughts? My periods have always been 5 days and regular. First time this has ever happened