How to fix the sound switch on my iPhone 4?

Well I was taking a shower and I like to listen to music in there and I don't know if I got any water on it. But now my sound switch isn't working (the one with the orange line), I can still switch it but it doesn't change to silent. I can't go to the apple store cause we don't have one near us, and I don't know if I can open it up because I don't want to break it. Should I give it some time or something

Please answer

Sorry but why do you shower with a non-waterproof phone? You should probably send it to apples service but that can get expensive because waterprobs with phones dosen't the warranty cover and you could get a 400 € bill for the service