3 DAYS BEFORE

I will be 45 yrs. old in a couple of months.  My mom naturally completed perimenopause and went into Menopause at the age of 42.  For the last couple of years or so, I've been spotting very lightly alternating dark-brown and pink in color for 3 days before my period actually begins the full flow.  

Whats normal for me is that I use to have 4 heavy days without prior spotting, the 5th day light and the 6th day almost none.  I counted it as 6 day periods.  Now, I spot lightly for 3 days prior, have a normal flow for two days and by the end of the third day its about over and finished for sure by the 4th day if not at the end of the 3rd day.

I am assuming I am perimenopausel.  FSH levels are normal.  Gyno tests are normal.  Your ideas would be appreciated.