I have had normal medium/heavy flow 5 day periods 28 day cycles, two months ago I had a weird period it was brown and dark red very light and went into spotting total of three days never had that before, the next month was also light which is not normal, this month I was 9 days late and when I got my period it lasted 1 1/2 days... what is wrong with me? Could I be pregnant? I have taken tests but they say negative??