The time from the first day of one period to the first day of the next is called a menstrual cycle. Your menstrual cycles will likely go on until you are 45 to 55 years old. Sometimes a girl will have some spotting of blood for a day or two after ovulation. She may also feel some pain in her lower abdomen. This is normal, but it is not her period.
Many families celebrate menarche as the time when a girl becomes a woman.
Sometimes parties, gifts, and congratulations celebrate a young woman's first period. Other families are more private about menarche. But whether or not menarche is celebrated in your family, it is an exciting and important moment in your life. Periods usually last from three to seven days. The flow usually starts light.