This is a normal fluctuation movement and nothing more in which fluctuating is part of the Crypto market that we should be used to it. Bitcoin price is proven unpredictable so i suggest that do not depend so much of some predictions of when it will bounce back as it might just to disappoint you again.
It`s normal and many traders wish for this fluctuations so they can earn a lot of money in short-term. 20% up or down is huge at current Bitcoin price,
changes are big and traders can make huge profit in weeks. Who buy at bottom and sell at top will earn a lot.
Not only dumps can happen all of a sudden, same is with price rise, all of a sudden price can start rising. If you can`t notice this changes than don`t trade,
is my advice to newbies. I don`t trade, I hold and I don`t care much about this sudden price changes.