As far as I know, everything was fine a few hours ago. My battery was getting low, I got the message that I needed to charge it & said OK. I did take a call while the battery was low. Got home, plugged it into the charger, & nothing happened...no signal lights...nothing. Just a black screen. Thinking it had powered itself down, I tried to power it up again. Nothing. I remembered having to reboot it once before, so I tried that also. Nothing. I have no idea what happened, or what to do! Any suggestions?