Hello Roxana,
I would recommend not selling any BTC at this point, but buy more BTC as the price goes down. The video above shows the very best points to buy in, as the price drops.
Looking at BTC price in the last few hours it looks like it is on the way up already! - So right now could be the last low - but there might be a couple more dips yet to come!

Best of luck - stay in touch - feel free to ask any questions you need answered. :D