Help my iphone volume is not working?

Hi, I have a iPhone 4s and my mum got me it for my birthday it's about a 1 year old and I have it on contract the contract has a year left on it… Basically I was about to put a song on in the shower and I put the water on standing next to the shower / bath tube and then I slipped and my phone went in the shower I instantly grab my phone turned of water and dried phone of as I was drying phone I went down stairs to get rice then I was looking at my volume and it didn't show any white bars at the bottom so now it only comes up with ringer I went onto setting > sounds, and I turned up the ringer up that's working… I have tried to call someone but you can only here it if on loud speaker I rang my mum on house phone to tell her my sound is messed up but I was to scared to tell her what happened all I told her was I went to turn music on and nothing was working… Should I tell her the truth? I'm scared btw I'm 13 I have tried everything and it's still not work what should I do? Help me please also my buttons on side don't work either!

It's because it went in the shower. Water damage will easily ruin an iPhone.