Open Question: I’m on cozaar 50mg/day for high BP and it still spikes to 180/113 frequently? Why?

I in the treatment of high blood pressure about 6 months ago, the emergency room. I went to my heart, he losartan 50mg/day me. I will be all right in my diet soda and since then has very low sodium diet. My blood pressure is still all the time to peak 180 / 110. It makes me feel terrible when it is. I have my left side chest pain, and sometimes and left shoulder. I dont drink and i dont smoke. My weight dropped by at least 15 pounds, continued to decline, I can not stabilize it.I I am 30 years old, I am 6'3 and 220 pounds. I do not think I was heavy. How the matter me?