It all started when the app called Viber started saying that it is crashing. I decided to restart the phone, so I turned it off. I decided to turn it on a few moments later, but then all the problems started. I couldn't do it. It just showed a green android logo and stayed like that. I couldn't turn it off and I had to take the battery out. I left it out for about two hours, placed it back in and still nothing. I've tried shut down+volume down button but it just shows android logo and exclamation mark in a triangle. What should I do?