It means
you are not pregnant and your partners sperm did not fertilize an egg during your ovulation process so the blood that would have been used to hold your baby during pregnancy now sheds out the vagina and this hurts
like a bitch. Only biological woman (an adult human female) with a uterus can experience a period, also known as a
menstrual cycle. No biological man will ever know what it’s like to have a period and it’s pain you must endure.