What Is The Medication For Continous Headache?

I have been suffering from an extreme pressure feeling in my head for almost a year now. It is concentrated at the top of my head, forehead, eyes, and the top of my nose. The pressure feeling originated during an episode of psychosis and has not left since, even though I have long since recovered from the psychosis. Prior to my psychosis, I had been a heavy cannabis user. I stopped immediately with the psychosis and have not used it since (never again). I used to have some minor sinus issues due to heavy smoking, and I understand a sinus infection can cause pressure in the head, but this would of course be a very long lasting sinus infection. To elaborate, I would have to clear my nose each morning and sometimes more frequently throughout the day back when I smoked. I quit smoking cigarettes too about seven months ago. The pressure feeling in my head started at the onset of my psychosis, prior to any medications. It has also lasted long after any medications. The original onset of the pressure feeling was unbearable with my head pounding and feeling like it was going to explode. The pressure feeling has taken my life away to the point where nothing is enjoyable, working is torture (I am a CPA), and basic tasks like cooking and laundry are something to dread for me. I have tried pain relievers, sinus medication / antibiotics, excercise, a healthy diet, proper sleep, spending months in a stress free environment, and had an MRI (nothing noted). The pressure feeling has remained an all day, every day, thing. I have had only brief moments lasting a few hours on a handful of days where I have not been suffering much.