Doge coin and some other altcoins are pumping and dumping it's price. That's how we can gain profits from them. So if I were you, continue to invest in doge coin. For me, it is still a potential coins. If you will research deeper, some gambling sites are accepting doge coins that is why I do think it will survive in cryptocurrency world. Don't mind the flactuating side of doge, all of the coins are doing the same.