Don't worry about what others say or feel. You have an audience of two: yourself first and the man who writes your check.

If you are adding value, you're doing it right. You are either a cost center or a profit center. Be the profit center and you will never want for a job.

I'm almost 50 and still in the game. If I'm honest, I still worry from time to time about being irrelevant, but if I'm still adding value, and I am, then what the other IT people around me think doesn't matter. Add value, learn as you go, gain in wisdom and understanding and you will always be cash-flow positive.

Don't make the mistake that so many do that you have to be working on something cutting edge or popular. Those jobs are nice, but I've learned--at least for myself--that I prefer the maintenance jobs. I enjoy taking something and making it better, even if it's just a quick fix, like two lines of code. Own everything you do. Be proud of your work.

You're still young with plenty of time to get where you will be going. Don't be in a rush to "prove yourself" to anyone but yourself and the man writing your check. Don't listen to naysayers, don't get trapped in the mindset that only the new, darling languages are worth investing in. Good programming skills are not language specific. Learn what you can. Use the correct tool for the job. Don't be a method man. Be the profit center.

I've been afraid of this. I've been working at a company for over 2 years. I'm 17, started here right after I turned 15. I've worked on many high profile projects. I've experienced a lot of respect, even with my age, but I don't want that to fade away in years to come.

Curiosity: are you from US? Is software engineering seen as less valuable than computer science? I'm asking this because for me software engineering is a more complete discipline and would encompass pretty much everything computer science does.

Sorry, sounds a bit like you're copping an attitude here. There's a lot more to software developement than any one or two things (scaling issues? complex infrastructures?). Don't be complacent and think because you've done X, you know all about Y and Z. I once worked with a guy who started with a company at age 16, did a lot of stuff, wrote a lot of code (went to work for amazon after that actually). Turned out a lot of the things he did, although valuable in the moment to make the sale, were terrible for the long term viability of the product. This kids unguided decisions literally set the company back years when growth took off, and the app couldn't scale, and security holes were gaping.

Just be wary of thinking you know it all, this applies to everyone, regardless of age or experience.