That's the meaning of "oh well" in this context, merdogan ("anyway".
As for the tense, I'm a little confused - it uses past tense in the first half of the sentence (ne dediÄŸini = what you said), but then future in the second half (cevap verecem). Are you sure it should be present/future? It seems like untrue conditional to me, especially because he goes on to say that he can't (understand what she writes).