I believe this happens to almost everyone, who is investing in this market, I have met many times like this. Every time I finished selling the coin went higher and when I bought it fell even further, it's normal in trading, as long as we always make a profit every time we close the trade everything is fine. The market is always moving so we cannot expect to sell at the highest price or buy at the lowest price and if you have a long-term investment strategy, don't worry too much about short-term fluctuations.