I have watched this subtitle like the capture. This is “ What do you mean what am I doing?”.
But I am curious the correct sentence should be "What do you mean what I am doing?"
Usually I am familiar with
< What do you mean by that? > or
< What do you mean by something? > or
< What do you mean Subject Verb ~ blah blah ~? >
That's why I think the correct sentence is “What do you mean what I am doing?”. Am I wrong?
The form of this question is
The speaker is responding to something that was said by someone else. This form naturally arises when the speaker feels that the other person’s question is unfair, though it can arise in various other situations as well.
Extending your example with an imaginary introduction:
Alex: Judy is upset. Brian, look after her.
Judy: Oh, Brian, this Covid isolation has left us old people so isolated. Would you mind giving me a hug?
Brian: Umm, Yes, I suppose that would be alright. (Hugs Judy.)
Alex walks back into the room, sees them hugging.
Alex: Brian, What are you doing?!
Brian: What do you mean what am I doing? I am taking care of Judy. What else would I be doing?
Here, Brian quotes Alex, changing the second-person “are you” to first person “am I” (so both refer to Brian).
The question form is what am I doing?
The statement form would be what I am doing [is baking a cake...]
The speaker is repeating the question that somebody asked:
what do you mean, "what am I doing"?
but the implication is that other person B asked
what are you doing?
and the speaker, when repeating it, changed it to a first-person perspective, so they're referring to themselves as the subject. They could have just used direct speech:
what do you mean, "what are you doing"?
but I feel like this is less personal, and less connected to who is saying what about whom.
