Well its nearing to happen already. At this date June 27, 2018 Bitcoin price is $6,122.78. Sad for those who invested earlier, its making a great loss for them while for them who haven't done yet it is a good time to watch for a more dip.
Yes it is nearing towards 5k but its unlikely it will go lower than 5k simply for that reason that it already costs around 5k depending where you mine and what equipment is being used. A large majority of bitcoin holders are miners and they will never sell for half the price of the mining costs.