Updated a Nokia app that was available this morning (Saturday). I can't remember what it was - accessories maybe?

Anyway, I went to load the Facebook app, and it didn't load, it would crash out straight to the start screen immediately. So I turned my phone off.

About half an hour later, I remembered that I had turned my phone off, so went to turn it on again. It came up with the black screen with the NOKIA text, then showed the Telecom splash screen... then restarted again. This went on for about 5mins.

I went down to the Telecom shop, and while waiting in queue, I got a text message. Yes, the phone had turned on and started up. So I left the shop, thinking that all was fine.

Phone has been VERY unstable this afternoon and evening. Sometimes it gets into a state where from the start screen, no apps will load. I can't load anything - I click on a icon, and the screen goes black, except for the clock in the top right corner. The start, back and search buttons as well as the volume, camera and power buttons are unresponsive. After about 15 seconds, the phone will crash back out to the start screen.

After the lock screen timeout, the power button no longer turns the phone back on. I have to hold down the power button as if to turn it off before the display will show again. If I swipe up, the start screen appears, but no apps are able to be run.

I have tried the trick of holding down the power and volume down button to reset the phone but this doesn't work. The only way to fix is to turn off normally and then wait for the phone to finally turn on again after cycling between the nokia screen and the Telecom splash screen.

Has anyone experienced this, or know of this happening before?