Can I fire my private attorney and middle of our trial?

Yes, but the Judge may not let you get another one, and you may have to represent yourself the rest of the way.

Theoretically, you can, but I doubt that the judge will allow you to substitute new counsel in the middle of a trial or grant you a continuance of the trial to find another attorney. I also doubt that you will be able to find an attorney willing to come in and represent you in the middle of the trial. You could conceivably represent yourself, with the court's permission, but that would most likely be a grave error on your part.