Arthritis: how to know if it's developing?

When you say, "announce itself" do you mean with pain or with a click or crunch or morning stiffness? You'd be best to see a professional (therapist or doctor) for an evaluation. Sometimes these things are hard to deal with on a forum.

Rheumatoid arthritis is generally systemic, affecting many joints, although hands are particularly affected. Something which you could do for a few weeks is to monitor what you eat and see if there's a difference with various foods/drinks. There is a school of thought which claims that dairy products can cause or aggravate joint problems like this. There is evidence for this hypothesis. It may be worth laying off the dairy for a few weeks to see if you feel better.

if you are really that inquisitive, you can always get an xray...it will display the changes..contact your rheumatologist...