My last actual period was October 17-21. Me and my boyfriend have unprotected sex for the post part . I had another period on November 16-19. A much shorter period and I didn't bleed hard at all and it was a brown color never red and not enough to fill a tampon or a pad. Today when I woke up I had that brown spotting again. And when I used bathroom again it's only on my tissue non on my pad. What does this mean??