I don't know if I am cursed or something. If I sell a coin now from airdrop/bounty few days later that coins increases much that you will regret selling. If I hold a coin from airdrop/bounty again that coins price decreases much that you will regret not selling right away. I'm confused now whenever I sell the price increases and when I hold the price decreases. Am I cursed?

You and I both Op, we are both cursed. Suffered the same fate as well. But seriously, once I sold the token, I do not care if it pumps after. I only sell when I am satisfied with the profit. If I failed to take profit on a pump, I just let it go and take it as a lesson. It is no use to beat yourself just because you failed to sell on the best price.