I havr a blood pressure of 170/100 and the doctor won't refer to cardiologist. How can I convince him?

Ask him for referal. Get a blood pressure calf and monitor your blood pressure in am and before bedtime. I would get three readings each time 2 min apart. Do this for a week or two and take results to your md. Watch your salt intake .
See Cardiologist. If you have an insurance plan that does not require your primary physicians consultation for a specialist visit, you can just choose the cardiologist and go on your own. If you don’t have such a coverage, then you should have an honest discussion about your medical concerns with your primary care physician.