I have the Samsung Galaxy s2 unlocked phone. I believe the carrier is AT&T but I am using it for Cincinnati Bell. the screen started to go a weird green color but I didn't know what was wrong. I held down the home button and the lock button together and then lines and stuff were going across the screen. I cant even turn my phone off, the phone is on but the screen is black. my text tone I can hear and other notification sounds gong off. I took the battery out and put it back in a few times but the screen is not coming back. Any suggestions?