When Price of any coin go up again and again then it means people are buying at every price of level but this trend is run up to the some fix time or on the top and after that it start to reverse back then it means now that is a time to sell the coin and book the profit because always buyer will buy the coin and smart people will book the profit. That's why every coin come back and now that session is going.
Red every where means market trend is falling down and this is the best time to invest in the crypto market for good profit for long time investment. First make a portfolio for your money and allocate to it into three ration then after invest and don't invest all money at one price.
Eth has really changed the crypto world because all new ico companies are coming in the market ether base block chain system for transfer the coin from one person to another person in the ether wallet. before it there was very less ico coming in the market and all were searching the solution to launch another decentralized crypto currency. but now every new company have best solution for existing in the market.