My iPhone 5 froze and my off button doesn't work?

Okay, I really need help. I recently drop my iPhone in the lake but luckily I was able to revive it with a vacuum hose and rice.
But I went swimming today. And I left my phone out and I thought it was a smart *** idea to take a video under water by putting my phone upside down so it doesn't get water in the speaker and by putting my figure on the front camera to cover up that hole. Then, my phone wouldn't turn off because it completely froze while I was video taping. When I came home I plugged it in to my charger and the Apple sign showed up and these words exact showed up; [NAND] _FindFlashMediaAndKeepout:600 physical nand block offset 1.It's been like that FOREVER. I'm really worried because I can't replace the phone if it has water damage.

Why the heck would you put your iphone underwater! Get atleast a waterproof case.

Most likley your screwed. You can hold the power and home button at the same time but most likley you f'd it. Hopefully this teaches you a lesson.

Take it to an Apple store and have them look at it.

Well if you have an itunes account on your computer then you have connect it to the computer and click on the button that's on the top right corner and look a little lower, the button says iphone and then click on it. It will show you all your information on you Phone and press the restore button and wait till it's done. Hope it works

I personally haven't used or owned an iphone 5 but I know people who do have the 4s and i have the ipodtouch 4rth generation, I'm pretty sure you do have water damage to your phone and it might just be easier to call it a lost cause, but if you want to try some things to see it works here's some

1. You can try restarting your phone by holding the lock and home button
2.bring it to a local mall with a cellular device kiosk and or a store like best buy to have them take a look at it
I'm sorry if none of this is helpful

I think your screwed!
Not only did you screw up by doing what you did originally, you have probably compounded the problem by not removing the battery and any memory card(s) immediately and then try to dry it out as soon as you could by using a hair dryer on a low setting to try to evaporate any water.
You then put it into the charger which only aggravated the damage already caused!
I suspect it is now too late for you to hide any water damage, although you can still try!
We all make mistakes at times, however some are more costly than others!