Bitcoin price trends is upward. It is consistently rising, 2017 is the year for multiple all time high BTC prices and I know it will continue next year.
You can still buy BTC when it fells down a little bit because I don't want to think that it will hit a hard drop. Just feel the market and keep monitoring...
My biggest mistake is to invest in BTC. I bought a BTC at 15K and now the price of n is 11K. I lost a lot of money