Hello Tinarenee,
I believe you. I'm not so sure I believe your doctor.
Too possibilities. As you said, someone is using your name (identity theft). The next possibility I hope isn't true in your case, but it happened in our area. A doctor who I went to and who performed surgery on me, a few years later was sentenced in court for writing "additional" prescriptions for others and using them as a means to supply his own drug habit. I don't know the details, however, I hope you get the drift.
I hesitate to say this, but being we are dealing with narcotics, there may be a point where you will need to seek the advice of an attorney. I would highly recommend that you keep every piece of paper and bottle of the prescriptions that you personnally had filled. Perhaps get a record from your pharmacy. You would have had to sign something at the pharmacy because you were getting a narcotic medicine. Make sure your signitures that you see are in fact YOURS.
Something just doesn't "smell" right.
RichT