That question is actually about gauging your ability to understand the oath, not about trying to exclude you from citizenship over a brief, historic mental illness. A "yes" doesn't bar you from naturalizing.

Given the timing, my instinct is not to try to amend or refile - but to disclose your confusion and the reason for your answer at your interview before they raise it. But really, I don't know enough about your situation to trust my own instinct, so I urge you to consult an immigration lawyer.