Do not panic! There seems to have been a some error by Twitter. Your Account has not been compromised. Twitter has accepted the error and has confirmed that the mails were being sent due to a system glitch. This is not the first time when the Social media giant Twitter have sent mails notifying about the password reset. earlier in November 2012, after a security breach, Twitter sent mass password reset mails to many who were not even effected with the breach.
