I co-founded a startup (that is gaining steam) and work at another startup as head of their customer service dept. but suddenly have the urge to begin to teach myself programming. Is it worth it? I am 25.

Yes, absolutely. It will give you a lot of insight, and make communication with engineers a lot easier. This is true even if you never get to a level where you would contribute to the company's product. But if you happen to be really good at it and/or enjoy it a lot, you can also take on an engineering role in your own startup, or just get yourself hired somewhere... why not?

It's great that you're working at two startups. It's like having twice the experience in a short amount of time given that the two startups are in different fields. You started to consider a programming career, what's the driving force behind this supposedly drastic change? Having tech skills, tech knowledge, or tech degree is useful in the future, yes. However, the best you can do is mix it up with your other skills, like making your own niche based on your own skill set, knowledge, and experience. There are a lot of helpful sites that will support you in your programming journey, most of them are free. The best thing about this is that they are self-paced, so there's no actual need to drop off the other startup unless working at two startups + programming = sleep deprivation. Of course, in terms of personal development, you'll reap a lot of benefits from learning how to code. It hones your planning skills and your attention to details, both are required to make it on top. For future endeavors, there's no question about it. you just have to know what that future endeavor is and find a programming language that would best suit you. Cheers!

EDIT: Try it out and see how it goes. Maybe start with a specific project in mind that has a clear start and end point to help keep you motivated and focused or try a course on http://coursera.org or http://www.codecademy.com Keep in mind not everyone has to be a technical founder, it takes a wide variety of skills to start a company. If you excel in other areas perhaps focus on strengthening those even more and partnering with a technical co-founder. Even in this scenario it definitely pays off to keep up to speed with the tech but rather more of a higher level understanding of the system, technology and methodologies used.

It is absolutely worth it. Programming is useful now in so many fields and applications that it is unbelievable. Learning to code is never a bad idea no matter what your current job or age.

Self-taught programming at age 30. And built a site that is actually picking up steam also. Here's what i did to keep me motivated for programming: Instead of learning programming just for the sake of learning programming, find an idea/app/site you want to build. Mine was to build a jobs site. Googled everything. "How to build a site with PHP/RoR, etc..." No joke, but I built http://www.jobscan.co/ by Googling EVERYTHING. My first starting point was the query "How to build a site in PHP." Forget the books, forget the online courses. http://www.codeacademy.com is great to learn.  They are sometimes too long to keep one's motivation going. But I wanted to build the real deal. I wanted to build something people could use right-away. If you have an idea in mind, do whatever it takes to get there. I even self-taught myself Photoshop to build my own logo, self-taught myself video editing software to build the tutorial video. And now I'm teaching myself Adwords... It's the process of learning. Start small, a simple language (ideally something visual). Heck, start with HTML and CSS. You'll get instant gratification to keep you moving forward. And yes, there's def a strong argument for going through the courses so you have a solid foundation and know all the best practices of programming. And learn the solid programming languages like Ruby on Rails or C++. But at the end of the day, if you lose motivation, none of that matters; small wins matter more. The LAMP stack was much easier to learn for me so I stuck with it. It was also the fastest for me to launch my site. From a start-up perspective, What mattered more for me was speed. I'll learn whatever to take me to get to my vision. And it did. Learned/built the site in 2 months, launched the MVP, and hit product/market fit.

I would highly recommend no— learning high level principles and concepts might be worth it if you want your developers to gain more respect for you but hiring would be much easier than learning all of coding, especially if you don't have any experience or interest in computer science.