You better get used to these spikes and dips because bitcoin is controlled by billionaires with billions invested in it. At this point, like all investments, once the whales figure out they can make massive profits, the small investor is at their mercy. The best bet is still to buy low and sell high or just hold and pray. Selling out of fear and taking a loss should not be an option. Bitcoin is dragging down all crypto right now, including block chains, but it'll recover after the panic sellers are shook loose.