I have a '03 f150 XLT 4x4

I was playing around in a field and got my truck stuck. I was deep in the mud, there were no rocks around or under the truck that i was aware of, and there is no apparent damage. Once i got pulled out and started driving there was a loud squeal that was constant till i put pressure on the brakes. Some of my friends told me there was probably just mud on my disk and everything. When i got home i sprayed off my brakes and it got a little bit better. But now when i go into reverse once i take pressure off the brakes there is a loud screech, when i go forward it is just a little bit of a squel.

I haven't taken it into the shop yet i just thought i would ask here just to see what you guys think.

 

after a couple hours i just tried it out again, and the squeal is still there mostly in reverse, but its not everytime i take my foot off the brake its almost random.