Yesterday while I was playing Dungeon Hunter 4, I clicked the home button down on the left by mistake, but the screen went black then the startup screen which written " Samsung Galaxy Note 10.1 " Appeared, and since yesterday nothing works ! I left it for the whole day but nothing happened.. still like this.. Even the battery charge was 0% that it turned off, but when I charged it, that screen appeared again !! Searched here for some answers but I can't do anything, the only option is to click the Power button + Volume down and what appears is asking me if I want to install a custom OS and warning me that it might be dangerous and so on, but nothing else !