I think its the opportunities missed tho.
I do regret not being bolder and saying yes to stuff when I had the freedom of no responsibility. Not settling for the 'this job is sensible and local'. Paucity of ambition. Being middle-aged at 22.
I could still have returned to dullsville if it hadn't worked out- but I'll never know now.
I like my life where it is now - and of course it may have been v different if I'd jumped the other way...