Mid-30s millenial here. Being an adult, instead of a 20-something young adult is overall pretty great. Having experinence and maturity makes a lot of shit easier, especially dropping uninportant bullshit. Definitely the best decade of my life thus far.

The downside: unaddressed physical, emotional, and psychological "battle damage" is cumulative (I only started treatment for ADHD at 30). So, if you have any untreated issues or trauma, it's best to take them on earlier so that you don't have to play catch-up.

That said, enjoy your life and keep in mind that, short of severe injury or imprisonment, you are not going to irreparably damage your future (repair is possible in some of those cases anyway). I didn't start my career (completely unrelated to my degree) until I was about 26. My wife, who is a year younger than me, earned her union card in her trade last year, after dealing with nearly 30 years of untreated physical and psychological issues. Despite this, we're both happier on average than any other point in our lives.

Me either 😞 I'm 41 and I still remember most of 17 very clearly because it was a very good year for me. But man, the years will just start whizzing by you the older you get. Sometimes it feels like 17 was just 5 or at most 10 years ago.

My advice is if you don't want to feel like you're getting older (and it happens to all of us) is stay active and avoid monotony. Doing the same monotonous thing day after day (ie most jobs) means you don't make as many "waypoint" memories - when you get old like me it's the big events that move away from the monotony that you tend to remember, and if you don't have many of those big events it feels like no time has passed at all since you have very little memory of that period. We don't remember the daily commute to work, the endless meetings, etc., but we tend to remember things like travelling or the first time with a new lover or emotionally-strong events like a death or marriage. In short: make lots of memories!