The best time to buy cryptocurreny is when the price gets low perhaps you should take advantage of the price drop because when it blooms again in price you will get a ton of profit that way your investing in the best way possible, i know that sometimes times you will regret your decisions on investing in certain coins but all you need to do is wait and trust the crypto because all coins value are unpredictable they depend on a small market in which small amount of money can affect the coins price drastically, all we should do is wait and hope for the best.