Lost GSM (Mobile Phone)

I hardly ever use my mobile phone or GSM as it is known in Bulgaria. yet when it comes to using it invariably, the battery has run out of power or I can't find it. Today I needed it to text someone and I just couldn't find it anywhere. It is usually kept by the side of the bed an used as any alarm clock, but this week it wasn't for some reason as Galia's GSM did the same thing. We even tried ringing the number, but couldn't hear the ringing anywhere. So right now I haven't got a GSM, how long this will last is unknown.