As I don;t Spam accounts and only use this account for personal email I don;t think it can be for spam.
No, but my point is, someone might have complained you were doing it just to get Yahoo on your back. I seriously doubt Yahoo is going to threaten your account because you gave Brokeback Mountain a bad review. I get bogus emails from Yahoo all the time telling me my account is suspended unless I respond to their email. It's just phishing.