Kinda Weird

So today I felt like I was experiencing some random “moisture” down there today while I was at work. I went to the bathroom eventually and saw a brownish color discharge. Which was actually old blood btw. I already received my period 2 weeks ago (normal time).. why am I bleeding today or at least experiencing this spotting discharge of oldish looking blood(the color)??? Someone help, I’ve never experienced this before and my next period isn’t due until another 2 weeks.