I've had my nokia Lumia for about a month when a few weeks ago i dropped it twice and a crack appeared to the left of the back button, but everything still worked fine. A couple of days ago I dropped it on a hard floor and another crack appeared across the screen. Hours later I discovered that the back, home and search button were unresponsive and didn't work. I don't know whether to send off my phone to a professional screen repairer (which would cost me around ?80) or buy a new digitizer of eBay for around ?10, but I do not know if that is the problem. Can someone tell me what is wrong with it? thank you!