I just started taking cardezem 90mg twice a day I have had a headache all day, my heart seems to be skipping, I was on metroprolo100 mg twice a day I have taken that as a bats blocker for years, I had a stress test and was short of breath, and the dr ordered cardezem. I have not felt right all day, should I go back to what I was taking? I am worried about the side effects of this,