First of all, thank you very much for taking the time to write, I really do appreciate it!
Whether or not some entity you deem dangerous holds the keys to decrypt your message will largely depend on the certificate authority you rely on to generate them. Indeed, as this entity provides you with both your private and public key, there is always a chance they may choose or be required by law to keep a copy of your keys.
I invite you to look up the license agreement of the authority you rely on and/or to contact them directly and ask this question. Indeed, as the pattern of laws varies greatly from state to state, country to country and depending on the chosen level of encryption, it is difficult for me to provide you with a general answer.
As a ground rule however, email encryption will not stop any government or determined individual from knowing what you are talking about. The questions are more along the lines of how fast they can retrieve the information and how determined they would be to do so.