Ok so I fell over with my galaxy S4 in my pocket. It was out of battery but it looked ok so I didn't think anything of it. When I turned it on, however, a lot of the display is just black and there are coloured bars and stuff all over it. Screen isn't cracked or anything. Does anyone know how I would go about getting it repaired? Would it need an entire new touchscreen? If you could tell me how much you reckon it would cost to fix it, (in ?'s) that'd be handy too. Thanks.