Can't blame myself for not being a fortune-teller, am I right? There's no point dwelling about what happened in the past, we couldn't have known or predicted it would become such a big deal. Unfortunately, I wasn't onboard since its beginning, in 2010-2011, when it costed a few cents, possibly if I knew about it, I would have bought some, since it was dirt cheap.
There are times that I ask myself "What if?" but I quickly brush it off. Not only is it meaningless, but it's also time-consuming, and as an old aphorism said, time is money.
You can blame yourself for ruing the fact though. No point wishing or regretting or second-guessing as you said, and we all look back on occasion. Hell, I even look back on Dogecoin every now and then but it's only to laugh and shake my head.
There are moments in life I look back even farther. Over 10 years before Bitcoin even. But the more I consider where I am today, the less I give a damn about the past.
Whatever the price, there will be no regrets as long as it is the target that has been achieved. I used to have some bitcoins too and I sold them for around $4000 and they were already very high. There's nothing to be sorry for, bitcoin continues to be developed and many altcoins have a good future.
Seen your very first posts and it makes sense you'd sell around $4000, shortly after your forum account, but how on earth did you manage to get "a few BTC"? Think I joined just a little before you and even 1 BTC was some kind of target that kept getting farther away in the wake of 2017 rally.
(Just curious)