Period talk!

Is it normal to have brown fluid days before period begins? 
This is the thing. 
On july 31st I had my period for only 2 days when it's normally 5 to 6 days but it did started with brown spotting (something that has happened only twice) and today im supposed to start my period but instead of blood it's been 2 days consecutive of brown fluid, not a lot and some of the blood its not completely red. 
On june & July I had unprotected sex way too many times with my husband. 
I dont feel bad, just my breasts are definitely getting bigger & they hurt a lot. 
I dont think im pregnant, has this happened to any of yall? Is this normal?