How about going to an actual doctor who treats joint pain, i.e. a rheumatologist? You probably have osteoarthritis ("wear-and-tear" arthritis) in some areas, but you may also have rheumatoid arthritis, which is an autoimmune disorder.
Also, the joints that seem to be hurting the most may not be the ones where the trouble really is - you'd be surprised at how weird referred pain can be. I thought I had arthritis in my knees, and in fact had been told that by other doctors since I was in high school (around age 13). When I finally saw a rheumatologist in my 30s, x-rays showed that the deterioration was actually in my hips, which was causing pain and even some swelling in my knees.
Good luck!