Whats wrong with my body?!???

I have had severe leg and foot pain the last 2 nights where I can't walk comfortably. And I had horrible hip and pelvis pains too!! So I looked in the mirror tonight and all of the sudden I now have stretch marks all over my hips.. And my bra didn't fit today either. I had cramps where I seriously thought I was getting my period that woke me up at 4am 3 nights ago which also isn't normal because I'm not suppose to start till 7 days from now. Why are my hips and boobs expanding but nothing else? Why did my legs/feet feel like growing pains. And what's with the pelvic/hip pain. Anyone understand any of this? I'm 20