My audio won't work for squat

Ok so I was at te beach and went sailing at The Sound (ironic is it not?) the plastic waterproof phone case used to belong to my daughter, but I found out she had chewed on it, I didn't see any holes at the time but my phone must've gotten water damages or something, because later after I plugged it in (it was dead and I had plugged headphones into it earlier as I plugged it in) I tried to watch you tube, no audio came out of the headphones so I tried unplugging them, still no audio. I went to my recordings and played something, it worked for head phones and the speakers, it even gave me an airplay option. But as soon as I exited the app the scrolling volume bar dissapeared and when I pressed the volume buttons the box didn't show up. It didn't work when I went to any of my other apps and music. I tried fiddling with the settings, but the regular audio wouldn't show up. The ringers work, and the box will show up, but the little bars won't.

And I'm not a genius when it comes to phones and technology, but I have a feeling something went wrong.