Every Time I Pee And Wipe Little Brown/redish Things Come

Every time I pee and wipe little brown/redish things come out i have no cramping or anything but it has been this way for like 3 days now and I have not taken a pregnancy test I feel normal it only happens when I pee and it also stains my under ware just a bit. I don't know what it is but I would really like to know .