I won't hesitate to sell my Bitcoin when seeing the price is high OP. As long as I was in profit already, selling is certainly at the right time but because we are aiming high, that is why we are preferred selling them during the bull season. Unfortunately, that is the thing that we never know but constant price monitoring saves us from not missing it unless we are too greedy to wait for more which might lead us to miss the opportunity as well.
Basically it should be in a way that you should be still proud of what you have if it goes up. Like for example lets say you invested 20k and bought a bitcoin, then it went to 40k, you could sell half of it, get your money out, so you won't be losing anything at all, rest could do whatever it wants, go up or down or whatever and you should be still keeping it.
That way, not only you are protecting yourself from a future loss, but you are also making sure that you could profit from going even further up, like if it does another 2x on top of that, which is possible, you still have 40k invested and yet your 20k is out which would be pretty sweet.