Security Concern: Admin Password Changed in Database with Format Inconsistency

I'm running Joomla 3.3.3.

All of a sudden, I am not able to log into my admin account on the front end or backend.

When I check the DB via PHPMyadmin and DB backups I discover that my password field is now different from previously.

And, that the format is different from everyone elses. Most users' passwords start with "$2y..." and some with "$P..." while mine starts with "y0/n...".

My question is, is there any reason Joomla would format my pw this way? If not, then the only other explanation is that something injected this new password into the DB directly. Should I be worried?

Is there a way to find out what, who, when, this field was edited int he database?

CB doesn't touch passwords. They're sent directly to Joomla API for encryption. Only reason for the format to change is the encryption method was changed in Joomla or maybe the password it self was changed. You can check the last updated column in _comprofiler, but that assumes the update was done using CB user edit.