Does Uterine Fibroid Cause Continued Long And Heavy Periods?

I know that I do have a uterine fibroid but it hasn't been a problem. Two weeks ago I started my period. I continued to have bleeding until the 13th day of the period. The bleeding however changed in color and consistency and didn't seem like menstrual bleeding by the end. I went one whole day without bleeding and then another period started yesterday. Does this sound like something to be concerned about? I did call my doctor and she wants me to have a biopsy of my uterine lining.