There is so many impact that affect bitcoin price. For example fake news, politics and many more. So just keep holding it until the price is upper than when you buy so you can get a big profit
Fake news, FUD government regulations are some of the news that has negatively impacted the price of bitcoins. And it trickles down the investors who panics and sold off without really investigating what's the cause of the declined.
I think that being the impactors of the price of bitcoin is from the increasingly high demand, from the demand taker it will make supply very limited and make coin prices have the movement of up and down the price of bitcoin.
Supply and Demand is just an off shot of this negative news I mentioned above, obviously if there's positive news demand will increase resulting on the price moving up, while a negative news will have a bad effect as traders is influence by it to sell bitcoins.