It is normal to have some discomfort around your menstrual cycle but it is not normal if this pain affects your quality of life or impacts your study/work.
Discomfort can be caused by an increase in prostaglandins. These are hormone-like substances which cause uterine contractions and restrict blood flow in the blood vessels of the uterus. Diet and lifestyle can be really helpful with this.
However, other painful periods can be a sign of endometriosis or adenomyosis.