Anytime random strange behaviors creep in, the first thing to do is a battery pop reboot. With power ON, remove the back cover and pull out the battery. Wait about a minute then replace the battery and cover. Power up and wait patiently through the long reboot -- ~5 minutes. See if things have returned to good operation. Like all computing devices, BB's suffer from memory leaks and such...with a hard reboot being the best cure.
Occam's Razor nearly always applies when troubleshooting technology issues!
New to the Community? Click here and also here for helpful guidance. Also please click here for additional helpful information to guide you as you proceed. I always recommend that you treat your BlackBerry like any other computing device, including using a regular backup schedule...click here for an article with instructions. If anyone has been helpful to you, please show your appreciation by clicking the button. Need a reference to BB10 OS/SR versions? Click here. Need a specific BB10 AutoLoader? Send me a private message.