D7000 water/impact damage err

Yesterday I was using my underwater bag camera case with my d7000. I set it down to the side on a boulder to climb up this rock and my friend slipped down the boulder and kicked it. The camera flew about 2 feet, bounced off a rock and landed in the water. I got it and it was still working but had got some water in the bag. We were pretty far in this swimming spot so I drained the bag and it was left in the bag with a little water in it for about 1 hour so it was pretty humid but it still worked for the first 20 mins. I finally got it out of the bag and it shows the ERR blinking on the top lcd. Frantically I removed the battery, SD card, and lens. I dried it off and when I took off the lens, there was absolutely no water inside the camera so I'm wondering if the err is from the bump on the rock or the water? And any tips on how to fix this? I'm a college student with no money to send to Nikon to get repaired but I'm 100% ok with doing any repairs myself.

You left it in a wet bag? Leaving everything out by itself to dry would have been a better strategy.

Here are a couple sites that have DIY replair blogs.
http://camerarepair.blogspot.com/
http://www.fixya.com

Do look up the Err message in your manual and see what Nikon suggests.