@jackie421blfdgurl, I am so-o-o sorry to her of this miserable condition that you are experiencing.
I am a patient like you, and I take Tacrolimus as one of my immunosuppressant medications. When my tacrolimus doses are changed it is in small increments. And I have to repeat my labs in order to monitor the effectiveness of the change.

Is there a reason, that you know of for the big change in Tacrolimus doses?
According to your words, "Out of my Mind", I can only try to imagine your misery. I highly suggest that you contact with the doctor or pharmacist about what you are experiencing? Does that sound like something you can do?
Oh - and also mention the cold sores. You might need a prescription medication if there is any infection involved.

Will you let me know if you get an answer or any relief?
Hugs,