Please log out, and log back in.
When changing passwords with anything but Apple's System Preferences dialog, the keychain is not notified of this change and on next login causes severe problems if you dismiss Apple's login notification. Even Apple's login notifications only repair the keychain seldomly.
Google's Keychain Minder is here to save the day.
Upon login (logout is needed to initiate) the following will appear
Selecting Yes allows you to recover your keychain by entering the old password and your new password.
Selecting No creates a new keychain for you using your new password.
Immediatly after pressing OK, your keychain is repaired and you can press Cancel on Apple's Cryptic error dialog.