Whenever my menstruation is approaching, while menstruating or nearing its end for the month, I will experience chilling pains.  I am sure many girls will share the same sentiments as me.  At times, I practically thought of just dying rather than enduring the pain every month.  Probably mine is more serious as it occurs every month.  
Today was the day for the month.  I was watching 'Night @ The Museum' when I felt the pain coming.  Being a movie-fan, I did not want to leave the theatre, but could not withstand the pain after awhile.  And as expected, it came.  (By the way, Night @ The Museum is not bad.  Recommended!  It's plot is very orginal and interesting.  Perfect comedy for X'mas!  Ratings: 4/5)
It did not stop then.  Continued for the whole day till now.  Luckily there is such a medicine called Panadol Menstrual.  Otherwise, I think I will not be sitting in front of my PC typing away now.  Anyway, being the curious me, I went to explore about menstruation and this is what I found from wikipedia:
Common usage refers to menstruation and menses as a period. Aside from its biological purpose, this bleeding serves as a sign that a woman has not become pregnant. (However, this cannot be taken as certainty, as sometimes there is some bleeding in early pregnancy.) During the reproductive years, failure to menstruate may provide the first indication to a woman that she may have become pregnant. A woman might say that her "period is late" when an expected menstruation has not started and she might have become pregnant.
Eumenorrhea denotes normal, regular menstruation that lasts for a few days (usually 3 to 5 days, but anywhere from 2 to 7 days is considered normal).[1] The average blood loss during menstruation is 35 millilitres with 10-80 mL considered normal;[2] many women also notice shedding of the endometrium lining that appears as tissue mixed with the blood. An enzyme called plasmin — contained in the endometrium — tends to inhibit the blood from clotting. Because of this blood loss, women have higher dietary requirements for iron than do males to prevent iron deficiency. Many women experience uterine cramps, also referred to as dysmenorrhea, during this time. A vast industry has grown to provide sanitary products to help women to manage their menses.
In many women, various intense sensations brought about by the involved hormones and by cramping of the uterus can precede or accompany menstruation. Stronger sensations may include significant menstrual pain (dysmenorrhea), abdominal pain, migraine headaches, depression and emotional sensitivity, and changes in sex drive. Diarrhea or loose stools are common for the first few days of a woman's period.[citation needed] Breast discomfort caused by premenstrual water retention is very common. The sensations experienced vary from woman to woman and from cycle to cycle.
Wikipedia also stated the various menstrual related products which I shall not elaborate here. If you want to find out more, search www.wikipedia.com .
 
                        