cramps before my period? wtf?

So I normally get very severe, very nauseating menstrual cramps the first few days of my cycle. When I was younger and in high school, they would be so bad I could not stop throwing up or get off the floor. As I've gotten a few years older, the cramps have lessened in days, to where I just have them for about two days and I usually don't throw up. I just pop some Advil and Tylenol and keep taking it as needed.   But my last two or three cycles I've noticed that about a week or two before my period I am getting these really annoying, very sharp, blatant pains that feel like they are in my uterus or somewhere around that area. Anyone have any idea?