Home button not working after water damage?

My iPhone 5s was in its Otterbox, recharge and ear bud flaps closed, when I noticed there was water between the screen of the protective cover and my iPhone! This was just after I had been out in the rain and briefly checked directions to where I was going, thinking its ok since its in a protective case. Wrong! Apparently there is no guarantee for it to be waterproof.... 90 bucks wasted. I removed my phone from the case to find it had been sitting in enough water to wet both sides! More than if i had used it without the case in the rain! I quickly powered it off, used the vacuum hose to extract moisture, and put it in a container of rice for 48 hrs. It now powers on, but the home button does not work at all, and the sound from calls has static. I dont have tools to take apart my phone. What should I do? And thanks so much for any help!