Have you tried uninstalling the last app or two that you installed? I also assume that you tried restarting the device too?
HTC One | Nexus 7 | HTC Sensation
my retired android devices
Samsung Galaxy S3 | Motorola Bionic | Thunderbolt | HP TouchPad w/ICS | Galaxy S Vibrant | DroidX | Droid1 | Mytouch 3g | HTC Dream G1
proud Android user since October 22, 2008