Wtf just happened

So, i've just been in a game and suddently the lights went out and i tried to log in again quickly but now it says my "username/password" is incorrect and im 100% sure its correct. And i just lost a free game for nothing, im pissed. I unnistaled the game and installed it again but if the problem continues i might unnistal it for good. This bugs annoy me as hell.