Wirelessly posted (Mozilla/5.0 (iPhone; CPU iPhone OS 5_0_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9A405 Safari/7534.48.3)
Add tag permission in your privacy settings and set every setting to private. I don't think you can undo what's done, but you can prevent future tags. If your boss asks, tell him you don't know why your account is like that.
And also, why would you add any coworker on Facebook?