What Causes Headache, Poor Appetite And Tremors While On Lopressor, Trazodone And Furosemide?

Hi. I am on quite a few medications for various medical issues. My medications are Xanax, Tacroliumus, Mycophenolate sodium, Predinsone, Protonix, Senokot, Aspirin, Wellutrin, Lopressor, Trazodone Hcl, Furosemide Tabs I am suffering from headaches, loss of appetite, tremors, sore throat, stomach pain, nausea, bruising of skin, mood changes, psychosis, blurry eyes, fatigue, lack of concentration and have shakiness and off balance. Since I have hat MANY tests to find the cause of these issues, with no conclusion, I am wondering could these be because of the side efforts? I had a pancreas transplant 2 years ago and my symptoms have been since then. I had a second operation in Sept of 2014 for a blockage. My GI system (I believe) is not working without the help of Fiber, suppositories, senna, and enemas. Is it common that side effects are not mentioned as the cause of my symptoms? If so, why do they have side effects listed if they are not recognized as the problem(s)?