Will bitcoin continue to fall to $ 6,000$-5,000$?Yesterday bitcoin has fallen below 10,000$. Today bitcoin continues to fall deep down to 8,200$ and possibly more.
I bought bitcoin at 15,000$. Who can advise me to keep or sell bitcoin at this time? Will bitcoin continue to fall to 6,000$-5,000$? what should I do? please..

At this point in time, no one can actually tell the range bitcoin would hit in this down trend - as support has not been detected. Considering the fact that you bought at $15,000, you're already at a loss and since you've not sold all this while, the best thing to do is to keep holding.