Femara and breast cancer

I am a 46 yr. old woman diagnosed with breast cancer last April 2008. I had left mast. a month after and then had chemo on June till Sept. My last PET scan was inconclusive so my oncologist put me on femara. I have been taking it for 5 mos. now. I experienced slight pain in my right arm early December of 08 and told my onco that it might be the femara causing it. He dismissed that and said that I have arthritis. Now the pain is also in my other arm which extends to both shoulders. I have problems with my range of motion in both arms now and is thinking of just quitting Femara. I have also pain in my inner thigh muscles and have spasms cause by sudden movements. Occasional insomnia and frequent hot flashes are other side effects I have to suffer. I don't know if it is worth continuing with the little percentage of advantage in the long run and at present live with a diminished quality of life.