Price of bitcoin increased because in 2017 many people get involved with it.
And old bitcoin users make HUGE profit, and new users Get scared.
What we need now, People need little study about what they wants to do.
I cant understand the point but if you are talking about those investors who bought from the last quarter of december those investors really lost big ammount of money. But those investors who bought before 2017 those people really earn big ammount of money and there is no problem selling thier with a 5k price right now.