I had my period twice in october. the in the nov, i had light spotting in the morning for 3 days. i have metal taste and last week i experienced bad back pains. i took a pregnancy test this afternoon and it was negative. what could be wrong with me?

One's Dr. can help: That said, a woman with cycles shorter than 29 days (shorter than 1 month) will likely have 1 menstrual period per month during the year, but will start 2 menstrual periods during one month of each year, because she has 13 periods each year. Two periods in one month per year is the only way for her to fit her 13 periods into a 12-month year.