It is bloodbath.
You an investor ?
Okay, calm down, don't panic.
Bitcoin and almost all other Crypto's are crashing only because their is a fear and possibility that Bitcoin may suffer due to disagreement between traders over Segwit implementation. In easy words, Segwit is like a software updation of bitcoin to speed up its transaction time. Some want it to be implemented and some don't want, interests differ. Now with Bitcoin falling, all other Crypto's are falling. Now as we proceed Bitcoin will fall alone while other Cryptos will hold tight on their value.
If you need money or can't afford to loose that then withdraw it by selling your coins. If you want to be in trade despite of this storm then i advice you to sell your bitcoin and buy any reputed altcoin e.g, Litecoin or Ripple. DGB is also a better option. Then watch the market die for few weeks and then you will be part of the uprising of market again. BTC will fall more but other coins are there alive and breathing normally.
Take my advice and buy some altcoins and don't stay there holding bitcoin. Or else cash out but that will take you out of the market.
Potentially i dont think you need to sell anything in the long run hold bitcoin and get it off any exchange or internal wallet have your crypto on an external wallet or a paper wallet stay cryptic!