(...) Is that the correct answer?
no
... and frankly speaking, neither do I understand what you've been calculating, nor do I understand you approach in general
you have a strong acid (and a certain amount thereof), you have a two-stage weak base (with, again, a certain amount thereof)
start by figuring out what will happen, and to what degree
after that, pls. come back with a detailled calculation of the resulting situation, so we can move further from there
regards
Ingo