Just diagnosed and a bit puzzled

Hello, I'm very new to this but I have had joint pain for many years that has got considerably worse this year. My GP referred me to rheumatology and I had my appointment today. The doc I saw was lovely but it was only after I'd come home that I thought of all the questions I should have asked him.

I told him about pain in my feet and ankles, my knees, hands, hips and elbows. It's worst in my knees. He sent me for x rays of my feet and hands and they showed osteoarthritis in my hands but no problems in my feet. He also thought that I have a "mild rheumatoid " factor and suggested that I continue on the ibuprofin my GP recommended, taking only as much as I am comfortable with. He's arranging for me to have physiotherapy for my knees.

I'm not questioning his diagnosis, but I didn't ask what this means about the sore joints that weren't x rayed...my questions now are whether there is arthritis in them and why were only particular joints X rayed? Is it important for me to know if there is evidence of arthritis in particular joints, or do I just assume that's the reason for the pain?

It's all very new and no doubt further questions will arise as time goes on....