I agree to the fact that the occurring of a bad trip should make you think about the causes of it.
Else, if you don't find why you lived that, it is relatively probable that you'll make it other times.
But I also think a bad trip can really be a very unbearable experience...
In this eventuality, if you want to calm down, you can take a benzodiazepine. It is relatively safe and it works well on psychedelics-induced anxiety.
Of course, it won't make disappear all the effects like the waving of a magic wand but it can make the experience bearable. And when you feel really bad, it is a delivery.
Furthermore, if you try to theorize the reasons of the bad trip during the trip itself, you will dramatically increase this bad moment.
I think the reflexion could be done after the trip, it is better for the quality of your analysis, and better for you.
It's up to you to have this reflexion thereafter and to not believe that, the bad moment spent, it is not necessary anymore.
(Edit: I hope that this message is comprehensible, the lack of english practise make me lose vocabulary...)