All that nonsense started for me October of 2010. Periods were all over the place, 25 day, 47, 18, 105, you get the picture. Some would end like normal, some lingered on.
I started charting my basal body temperature (free sites on the internet), I soon realized that I was rarely ovulating, I had a long stretch of no ovulation and then had random episodes of spotting.
Last fall after spotting for about 5 weeks, I went to the dr. had endo biopsy and ultrasound, blood work and pap. Biopsy was normal,ultrasound showed fibroids, bloodwork showed FSH 56.3. = Menopause.
My dr said when we don't ovulate regularly, our lining doesn't shed regularly either ... it can come heavy, spotty, not at all and everything inbetween. The never ending spotting scared me .. she told me it was the fibroids doing that.
It stopped 5 months ago, I wait every day for it to return. I hope it never does.
My guess is, you're fine, it feels SO abnormal to us because it's not what we are accustomed to with our cycles. Drs usually like to check to make sure all is healthy, usually it's just pesky perimenopause.