Can you give me advice? I have been getting a lot of pressure type headaches left side of head and at the back of head. Could this be sinusitis?

Behavioral medicine. Presuming that you have been thoroughly examined by your doc, you might consider some behavioral interventions. Your BP might also be elevated due to the pain. Herbert benson, md, a cardiologist has a great little technique called the relaxation response that might be helpful in relaxing the vessels in your head. Sinus headache is above and below the eyes.