black screen when phone is on

hi there problem with my S2 i was playing a game on my phone when all of a sudden the screen went black and couldent do anythink , but the menu buttons all light up and i can hear the phone powering up but nothing on screen, ive made a call to the phone and it rings but still black screen , ive hooked the phone up to the tv with a hdmi cable and the picture and menu show's up on the tv but not the phone , plus when it is conected to the tv and i can see what im doing the touch screen doesent work. please help.