help with league of legends bug

when i launch the league client everything is fine , i get to the champ select and then when the time runs out its suppose to bring me to the champ loading thing where you can see the opponents champions and stuff but instead , everything just exits out and im left with my desktop screen where i can click everything without a problem . then when i re click to play league of legends it tells me if i want to terminate the current application that i had aready but it doesnt even show anything except for my desktop screen .. help