it was the bitcoin price drop effect. when bitcoin went down to below $2000 altcoins dropped hard. ethereum specifically lost a lot of price. and when it happens many start buying at the bottom and when bitcoin price reversed, price of ETH went up because of these two reasons.
but as the other comment said, there are many ICO token holders waiting to cash out and they do it as the price goes up and cause another drop.
thanks to your message, Because i am ethereum lover.