Not a financial advise, but for me, yeah, there is a big possibility that we will go and even exceed the last all time high.

So if I'm in your case, despite the paper loss, I wouldn't sell, and I will look at the long term investment and that will be my plan. Obviously, you don't like to be on a loss right? So the only thing you can do is not sell and have the patience to be a long term holder, or at least hold on it till the next bull run and see how your money will be.

Just take this as a lessons learned, a valuable lesson not just for you and for everyone as well that if you want to take profit in a bull run then do it instead of regretting like what the OP is saying here and blaming it on himself because he wanted more.