I prefer placing punctuation next to the closing quotation mark like this:
I'm watching "Titanic".
However, when there is already a punctuation within the quote, is it right to add another punctuation after the quote?
Did you say "Hello?"?
No, I didn't say "Hello?".
Then did you say "Hello."?
Yes, I said "Hello.".
A punctuation, before the closing quotation mark, for the quoted sentence. And another one, after the mark, for the main sentence. It might have made sense, if only I have ever seen such usage. (Especially the last one, which contains two full stops. It looks so wrong.)