Why is it that whenever I copy/paste my keyframes in the graph editor, their values on the axes change? Is there any way to prevent this from happening?

When I rotate the elbow joint of my model, the area around the elbow becomes flat. Any way to prevent this from happening?

http://i.imgur.com/Di8HLUk.png

Awesome! Thank you so much. :D

So, I've started making a model and all was fine until I had to mirror the other half of the model.. I don't know much about Maya other than the really basic stuff so yeah, any help would be much...