Communicate with her.. see what the problem is and if your at fault, do something to solve the problem or walk away from here. Its logic here. Dont understand why we need to apologize every time a girl is unhappy.. what? to make them happy? It doesn't add up in the end.
Maybe ask her, has everything been ok? is there anything you want to talk about? If she gives you the typical girl talk "no everything is FINE".. then leave it at that and forget it. Clearly if she says fine, some things wrong, but when a girl says "everything is fine, dont worry", to me.. i literally dont worry as i cant be bothered dealing with games.