That is why everyone needs to achieve experience before getting successful in bonsai. And this is one of them experiences that give you future success.
Human mind works with problem and solutions. That is what you have done. There was a problem and you had to do something. That is wrong approach, but perfectly normal.
Repotting do not save a struggling tree, quite the opposite. Pruning do not save a struggling tree, quite the opposite. Taking it indoors do not help the tree, quite the opposite. You did not help the tree. Now all you can do is put it in a shady position, keep it well watered and hope for recovery.