What are the signs of arthritis and is it preventable?

I had a serious wreck 10yrs ago and fractured my hip in several places and had to have major surgery. The doctor told me that I would be more suceptable to arthritis. I am now 32 and have been having for the last few yrs or so pain in my arms and legs but only at night when I am trying to sleep. Could this be the onset of arthritis? What are the signs? Thanks!