Tendonitis usually occurs in one joint and is caused by overuse like in tennis elbow, Traveling joint pain is usually a sign of one of the arthritis diseases like polymyalgia, myositis or there are a lot of other diseases in this "Family" You should probably see a rhumatologist and have some blood work to see if your SED rate is up. It tells you the degree of inflammation. Most of these illness do not have a specific test but diagnosis is made on the symptoms reported. Don't let your doctor give you a generic diagnosis of just arthritis. Good luck.