What Treatment Should I Undergo With Lumps On Rib Bones ?

I am a 25 year old female with multiple lung nodules in both lungs and lymph node involvement they nodules are not growing but spreading and more are showing up and are now called masses in my lungs, I have lost alot of weight and am very fatigued and in alot of pain, I have developed some kind of lumps/bumps on my bones about 1 1/2 inches from my spine on the rib bones not sure what these are but pressure causes pain and cant breath lying flat in bed, Hard to breath all the time and chest pain , ect.. My doctors are telling me this is not cancer but have never tested or biopsied any of these, and tell me I am to young to have cancer. I have had a tests done for all auto immune and all negitive, TB tests negative, dont have AIDS, I have never been tested for any cancer which I have asked for and told I am to young to have. I am not sure what to do from here. Thanks for any kind of answers you may have for me, Shelby