Joint pain can be caused by all kinds of things other than just arthritis; and as someone else has already said here, there are different types of arthritis. Rheumatoid arthritis (unlike Osteo arthritis) is an immune system disorder, while osteo arthritis occurs in individual joints. Ordinarily, osteo arthritis results from either injury or "wear and tear" (which most often happens with middle-aged/older people).
1. You can't be sure that what's causing your joint pain is arthritis at all, so you need to have a doctor diagnose exactly what is causing the pain.
2. IF it is arthritis and you've never injured the areas where you're feeling pain, then there's a good chance it's another form of arthritis which should NEVER be ignored. A form of arthritis like rheumatoid arthritis (which can hit someone at any age and has nothing to do with age at all) requires treatment in order to prevent further damage to joints.
If you haven't been to a doctor to have him/her confirm you guessed "diagnosed" of arthritis you can't be sure it is. If you have arthritis and just let it go, then you could have more damage to your joints than otherwise would have had to have happen. There are all kinds of medications and non-pharmaceutical treatments for arthritis, but you first have to make sure what you have is arthritis. There are people who don't go on prescription medications if they have something like osteo arthritis in one joint that's been injured and eventually developed arthritis. Having pain in more than one location suggests you've got something other than that particular type of arthritis; so yes, it would be more than "worth it" for you to see a doctor. It would be very important.
Your choice to use the words, "early onset arthritis" suggest that you believe arthritis comes naturally to everyone with advanced age, and if someone younger gets it then it's an "early version" of the same thing. That's not how arthritis works. Yes, older people tend to be more likely have more wear and tear (or previous injuries) that might cause arthritis; but osteo arthritis is osteo arthritis and something like rheumatoid arthritis is rheumatoid arthritis. So (respectfully), forget your made up "non-diagnosis" of arthritis and see a doctor. For all you know it's not even any form of arthritis at all. Even if it is, though, it requires a doctor's "official" diagnosis and guidance.