I do not see panic selling is a problem, this condition can be predicted. Panic selling happens because some do it just to hold their cash or temporarily switch to altcoins when bitcoin is experiencing fall dip, they will come back again to buy / exchange into bitcoin when price recovery occurs. What worries it is panic buying, when there is a massive demand and skyrocketing prices, will make a full network transaction. Conditions where there is a possibility of bubbles occurring.
this was been happen always but the best thing to do is having the knowledge for when would be the best thing to buy and sell , well in selling we cant even control that specially when there is some emergency , stay calm and be patient yes you must to be patient even you may say that you really have to buy but always think for some possibility that can happen and the negative also.