Can a submissive dog turn to a dominant one?

i kinda ask this question but need better answers. so why does my dog let the 1yr old terrier jump on her even though she doesnt like it. but later she growls witch i dont understand if she is more submissive than dominant. like when we play fetch the new dog will chase her even though she doesnt like it. but if he has a toy she wants she will growl nd get it. but sometimes she is playing with a toy nd he just goes up to her nd get it witch i dont understand at all..........