I participated in tests of a variety of blood pressure medicines over a period of eight years. When I stopped, the doctor supervising the tests reviewed my records and prescribed the medicine that appeared to have helped me the best. I have been taking that med for several years now and my bp is good with no side effects. During the tests however, I had some of what you describe, some extreme headaches, and many meds that didn't do anything at all... for me. Read the information sheet that came with your medicine. Please discuss your symptoms with your doctor. Find out what class of medicine it is that you are taking. There are several common types; ACE inhibitors, Beta channel blockers, diuretics, etc. Each class may manifest different side effects while some side effects may occur in more than one class. In the end, your doctor may have to try several meds with you to find the one that works best with the least onerous side effects.