bitcoin price was not stable. now can not speculate much, bitcoin price can be increase or decrease at the end of the month when Chinese baned Bitcoin exchanges. However, i think that bitcoin price will reach $5000 by the end of this year.
This is the nature of bitcoin. Every time it goes up and down with quite some margin. But consider it normal since bitcoin is innovation and powerfull, so many entities try to boss bitcoin.
Which in the end is impossible, because it's decentralized nature, we are safe...
I'm not sure whether there is a connection between the fact that bitcoin is a decentralized currency and that its price goes up. It seems to me that the price goes up because of the popularity of this currency.