(1) I very respectfully feel that most native speakers would not
understand your first sentence. But after reading your second sentence,
I think that I know what you wish to express.
(2) Tina thought she was being compassionate in her actions but
in reality she wasn't. Is that the general idea?
(3) If it is, then maybe your sentence could be something like:
Until this event, Tina did not know that she had exercised/ shown
misguided compassion for the cat. (In other words, she had wanted to
help the cat by her actions, but her actions -- whatever they
were -- actually hurt the cat or made things worse. )
(4) I apologize if I did not understand your question correctly.