During the last week I bought coins and they almost immediately fell by 10-15%, and today early in the morning I saw how they fell by another 15-20%. How long will it last?., and whether I should sell for what I have. I wouldn't want to be left with empty pockets. 
No one can predict how long this market value price will continues to goes down.What we should do is to hold and hold so that our pocket is not empty.Sell it now will mean lose, leave with nothing. I think that the whales are doing just that, pushing the price so they can buy tokens for a very low price. I would not be surprised if the price will continue to fall on Bitcoin, now it is almost impossible to predict the actions of the market.