i do this mistake lot's of time in my crypto life. i still now what to do but sometimes i could'nt resist my hand 
we must control everything we will do, especially the panic that we experience today. We recommend that in dealing with things like this we need to relax and refrain from doing things that will harm us. because indeed every regret is at the end.
It is important that you have patience and calm in everything. The panic sell will not benefit but only make you more and more losses. So I advise you to think very carefully whenever making a decision regarding cryptos.