Pain in big toe 1st mp joint-x-ray says rheumatoid arthritis. dr thought it's from injury as kid. should i be worried ab something more serious?

Probably not: Arthritic change in joints is common as we age. Unless it is inhibiting walking, running, or daily functioning you are ok.

Let me try to help: Do you have any other joint involved with rheumatoid arthritis. If you do, you have to evaluation and possible treatment for R A. If you don not most likely an injury when were young. Good Luck