Hi, I Am 40 Years Old Female. I Have Extreme

Hi, I am 40 years old female. I have extreme blood pressure spikes (up to 210/130) for the past two months, which I can almost predict by increasing pain in the abdomen and especially somewhere deep below the breast bone. Spikes are almost always in the late evening or during the night, I found out that lying down aggravates the condition causing very unpleasant feeling in the chest and almost immediate spike in the diastolic reading, later followed with the systolic spike (diastolic is higher also during the day). My GP prescribed me the Lacidipine 4 mg and tranquilizers but it seems that I only get very low BP readings in the morning while evening/night spikes are still happening. Now I got Zoloft which I hesitate to take since I can't relate the spikes with anxiety or panic, but there's not much I can do. Pheochromocytoma and kidney diseases are excluded, blood work is normal, I have mild chronic gastritis that would unlikely cause this chect pain. Please advise what else I can do to resolve this problem. Thanks in advance, best regards.