How I foresee the market is that if Bitcoin moves down all the other cryptocurrencies will follow. This is because otherwise the proven Bitcoin value will not be reflected correctly in the other cryptos. So, the fallen waive is a signal for the entire market and once it starts to move it will affect all of them. But, as with the flux and re-flux of the sea after it shrinks it will expand once again.
Maybe is worth selling in order for afterwards to buy more cheaper, but nevertheless this is a risk for the opportunist, mostly the ones that work hard to get their coins will not want the risk.
So, Keep calm, all is good! @cryptorg