Are you counting by the calendar days? Usually the cycle is in sync with the phases of the moon, meaning you will have 13 cycles a year, not once a month which would be 12 cycles.
No
a menstrual cycle (more comonly known as a period) lasts about a week and happens once a month.
A woman has her menstrual flow during menstruation, which is at the start of her menstrual cycle. The typical menstrual cycle is around 28 days, meaning she should menstruate roughly every month.
Your periods aren't determined by the dates on the calendar, they are determined by your menstrual cycles and your cycles will never perfectly sync up with the calendar months. The average menstrual cycle is 28 days which is shorter than a month, cycles can change, and months aren't all the same lengths - there's no reason at all to think your period would always occur on the same day every month.
Orientation has nothing to do with menstrual cycle.
Yes, your period isn't determined by the calendar date but is determined by your menstrual cycle - if your menstrual cycle was only 21 days long then you could menstruate on the first of the month, then again on the twentyfirst of the month.
A lunar month is 28 days... important for the menstrual cycle and such.
No, months have no effect on your menstrual cycles.
Menstrual flow typically occurs during the menstrual phase of the menstrual cycle, which is when a woman sheds the lining of the uterus. This usually happens about once a month, lasting anywhere from 2 to 7 days. The menstrual phase is the first phase of the menstrual cycle.
If that happens often you should go to a doctor for a checkup.
Your period doesn't start on a specific calendar date, calendars are man-made and your menstrual cycle is controlled by nature/biology. When you menstruate is determined by your menstrual cycle, the typical cycle is 28 days but everyone is different and up to a weeks variation from your average menstrual cycle is normal - it's not possible for your periods to start the same day of the month every month.
The average menstrual cycle length is 28 days, which is around a month long. A menstrual cycle is around this length simply because this is how long it takes for your body to ovulate and in turn for it to menstruate.