52 yr old woman each evening has hypertension / 200 - 280 bp. Takes injection to bring it down but no idea of why. Type 2 diabetic also. Likely cause?

What injection ? I am not aware of any injections that pt can inject at home for bp. Cause of BP is most commonly age, and heredity.
RAS. She needs to be evaluated completely by cardiovascular or renal specialist -- she may have renal artery disease that would make treatment of hypertension quite resistant and difficult.