My people, my people! We should have a (digital) support group. You've just described me perfectly, even to the point of compulsively investigate people's age. I know that feeling in the back of your head, I often describe my state as :I hate myself every single waking moment, and then some more in my sleep. I think this is not that rare of a problem for our age, and generally, I disagree with the sentiment that optimize your life for happiness will solve it (it's just a different life goal. Nothing wrong with aiming for happiness as a goal, but it's not for me personally)

This is definitely not advice, consider this a commiserating post.

Ten years ago, I started learning to play Go (the board game). At the time, I was obsessed with the game, and I was very sad that I didn't get to know/ learn the game earlier. I wanted to play Go professionally, and I thought that it was too late for me to ever be one of the top players in the world (context: I was 16 at the time, and to play Go professionally, you have to be really good. Most pro started playing when their age is in the single digit). 10 years passed by, and I'm not sure what changed, but that certainly doesn't seem to matter anymore. I still love the game, but now looking back, I don't feel dreadful that I didn't learn the game earlier. This might sound unrelated, but I'm sure that 10 years from now, we will look back and laugh at ourselves if we think this is too late to do X, Y or Z.

There are a saying (paraphrase by me) that goes along the line: when you're 20, you're mostly a product of your family, environment, upbringing, friends etc... but when you're 30, you're a product of yourself. That is to say that in our younger years, in a sense a lot of it comes down to "luck", you might stumble in something you like to do young enough that you get some success, got motivated, didn't waste time on video games (along with the usual notion of "luck" involving one's upbringing and family, obviously). Teenagers and young adults are mostly idiots, to no one fault, and only some of us were fortunate enough to skip that period. The world is choked full of distractions, and while I used to think that I have unlimited will power, I also thought that I was invulnerable, so well ...

Life is long, and one of the things I've realized is that almost no one runs full speed for their whole life. The few that do are probably thousands in a billion. I think it was Bill Gates that commented Jobs to be the rare one who has the fire his whole life. A lot of the people who are massively successful in their youth will slow down (it's stressful to be ambitious, after all). So well, if we want to catch up, I guess we already spent our shares of "relaxing time", and just have to look down and plow through things now. Just think about it as we doing things a bit backward. It's gonna work out fine (I hope!). We can't make up the last 10 years, and likely won't get to the top of the world. But I believe anything under that is still up for grab.

There are also the aspect that at least for me, it (work, ambition, success) is a really personal and emotional thing, and chance are our judgements right now are terrible (emotional == irrational) -- maybe a few years from now we would have realized that the "TV watching time" was us exhausting from work, and that we couldn't actually programming 14 hours a day anyway. Just to point out a seemingly irrational thing in your post, you're 26 now, and hoping that you would have started in earnest at ... 25 is a bit odd, isn't it? One year, while valuable, won't make that much of a difference.

Write your worry down. I don't know why, but as soon as I write things down, it feels like I'm taking it off my head. I guess now there is a reminder of my mistake on paper, and I don't have to constantly remind my self.

Also, booze helps, a bit of drunken state helps me slogging through side projects. Although extreme moderation is advised.

My email is in the profile, if you're looking for someone to commiserate from time to time ;)