Don't try to panic, you have to keep on buying if you are believing that the price of bitcoin will be soon reaching $10,000 or even higher. And you just have to sell if there's a need for you to have some extra cash or you want to diversify your bitcoin into some alt coins. When you sell, you need a reason for it. Don't just sell because you feel that you want to, I'm trying to avoid this type of feeling because long term holding and buying is the best thing to do every time with bitcoin.