Trying to call my iPhone?

I've lost my iPhone today and I just tried calling it, (It's somewhere at home cause I never bring it outside) And you know how when you call someone or a phone number, it rings, then voicemail? or if the person hangs up, it goes BEEP BEEP BEEP? Well, when I tried calling my iPhone it just went straight to the beep noise, no voicemail.. It rings for 3 seconds then beeps.. Usually if it's off it goes to voicemail right? (Fido).. I might have left it in the washroom, but what if my baby sister put it in the toilet and flushed it? destroying the device, therefore making it unable to call.?