I have hypertension and I have been taking Cardizem for a year or so but recently I am feeling very tired and fatigued. I have developed a pain on the lower right side of my back (could this be my liver)?. Sometimes I am also finding it hard to inhale a sufficient amount of breath and I feel a heavyness in my chest. Should I be concerned and maybe chage to another medication for my blood pressure? I had a echo cardiogram and a stress test earlier this year prior to surgery and I was told that one chamber of my heart is a little sluggish. Could this damage my heart more?