I started my period on September 8 and it is now October 5 and it hasn't stopped. It is extremely dark brown but has no abnormal odor. On the 8th it was very light for about 3 days then stopped for two days so I suspected it may have been implantation bleeding because my husband and I had a lot of unprotected sex October 1st through the 4th but then it started again and now it hasn't stopped. I did however notice a lot of red blood two days ago but once I changed that tampon it was back to dark brown. I took a pregnancy test 1 or 2 weeks ago but it was negative. Help Please?

Please visit the doctor. I had the same problem and I kept delaying it and finally I had to do a lot of tests. It might be due to thyroid or PCOD.