OK so I am 16, and I feel very ignorant about this. I have been getting my period since I was 13, and I only know that I get it because my body is like cleaning itself or something. But what exactly goes on though a month of a woman's life with her body? I don't really understand that very well...

A period is meant to get your body ready for conseption. The uterus and the ovarys act to conceive every month... I have been reading up cause I may be pregnant so here is some help. From Ovulation to Early Pregnancy: A Week by Week Cycle Tutorial

Thank you

Every month, one of your ovaries get ready to release an ovum (egg) which if fertilized by a sperm will become a baby. Your uterus, meanwhile, prepares itself for possible fertilization by thickening its lining (called the endometrium) so that the fertilized egg will implant have a place to stay and get nourishment while it grows to become a baby. If fertilization doesn't occur, then the lining prepared by the uterus must be shed and that is what comes out as your menstruation.