If you sell bitcoin when it is dipped then it will obviously loss, it is not recommended to sell when the price falls, because that's the same you become a panic sell. Be patient to sell, because bitcoin prices still have a great chance to increase again.
Bitcoin is sought as a long term investment so one needs to be patient while investing in it. Although the price now is loitering about 8000$ but selling it now can cause you to regret in future as I believe it will soon rise up to glorious heights. So, it is the opportunity that should be abstained for now...