iphone 4 suddenly stopped working (several wierd things happening)

first off, hello!

today my iphone 4 suddenly stopped displaying / connecting to my 3g network.

i couldnt send nor call anyone. i can however receive calls. checked with my service provider, they have

not closed my subscription.

i got a call, and spoke to a friend for a few minutes.. then all of a sudden, i didnt hear anything. no static noise, nothing.

completly dead. my friend could however hear me loud and clear. i installed viber to make a network call, same deal happens..

cant hear anything. i also noticed that suddenly i didnt hear any sounds, like ringtones etc, it only vibrates (even though i have sound enabled).

i cant play my ringtones either, dont hear them.

whats wrong here?

recently updated to ios 6, but its been working flawlessly until now