First pregnancy .. need helpp !?

Hi im 15 going on 16 next week and i need helpp with thisss . umm one of my friendss said thaat lower crampingg down in your lower tummy caan be your uteruss stretching and also you get back paains in your lower backk . iss that truee cuz im experiencing somee lower backk pains nd some minor crampingg . isss my hips going to get wider too?