A; The first thing to do is to see a medical doctor for a complete medical workup. Sometimes delusions like these are caused by things like a vitamin deficiency, an electrolyte imbalance or a brain tumor, to name only a few possibilities. I’d hate to have you go on heavy-duty psych meds if the problem is physical.
If you are medically okay, then you need to take your letter and this response with you when you see your psychiatrist. A psychiatrist relies on you to provide enough information to determine an accurate diagnosis and to work out a treatment plan. Unless you are completely honest about what you are experiencing, your psychiatrist is left to guess – not a good basis for prescribing medicine.
If you do have a mental illness, I strongly suggest that you get started with some psychotherapy as well as medication. You need more relief than meds alone will give you. A therapist can provide you with important support and can help you learn additional ways to cope.
I wish you well.