Suggest Treatment For Spotting And Light Brown Discharge

Hi, I'm 50 years old and have ALWAYS had regular periods on a 28-day cycle up until last menstrual period I had my period early on cycle 21, May 12, 2011. As of Friday, June 24th, I noticed light brown discharge on toilet paper and a thin stripe of red-tinged blood. Thinking I was going to start (as I usually start out with brown and within a few hours, or almost right away, I start flowing naturally bright red blood), I continued to spot brown discharge. Now, it's Sunday, June 26th and the brown discharge is coming more like a flow of blood but still brown. Question: Is this a sign of perimenapause, pregnancy, a late period, a miscarriage? Should I see a doctor?