I Never thought that I Have to see bitcoin is under 7K USD again in This year. Because we already did this about a couple of months ago! And now Repeat Bitcoin is under 7K USD! And the market trend says that Bitcoin can go under 6K USD too. But what is the actual reason behind this vast fall? I haven't seen any robust lousy news or anything like that, Then why bitcoin is continuously decreasing? My friends are laughing at me, who sold their bitcoin when it was 14K USD! That time I told them you guys are doing wrong, Hold your bitcoin, Bitcoin Price will rise again. And now I am regretting really 
First of all you must understand that bitcoin price is volatile. They way you are constructing a statement, I see that you are just used to see that bitcoin price is always uptrend. If you just started last year 2017 then Im not surprised that when a price falls like this, those 2017 peepz are worrying too much. Bitcoin price is on continous uptrend last year that's why many people enter crypto without realizing and understand what risks they are going through.
If your goal is long term then just stick to it. Bitcoin will surely bounce back but we just don't know when. No need to specifically knows what is the exact reason why bitcoin price fall.