What could cause : general aches , mild to severe pain and back stiffness , muscle weakness , fatigue, continuous or occasional sharp pain in the head, abdomen and hips as well as occasional tremors.

These are very nonspecific symptoms and may involve a variety of problems. The general aches could be side effects of a viral illness , fatigue, stress / anxiety, or musculoskeletal problems, etc. . Tremors could be due to low levels of blood sugar , anxiety , chills as side effect of infectious process. The facility to have bruises could be due to a low platelet count or other abnormalities in blood count . The important thing is that you will do a complete medical evaluation by your doctor. Hopefully , after taking a detailed history , and a physical examination and tests , the doctor can make a diagnosis / s can provide a treatment plan . Good luck. I hope you are well soon .