I was given 25mg, told to start half. My HR jumped to 138. I felt chest pains(apparently normal) with tiredness. Called my doctor, he told me to go to ER. There, my HR ranged from 88 to 107 suddenly, many times. They gave me IV to flush out med. Tests were normal. I went home, and my HR dropped as I slept to 54. I woke up, HR was 72 active. Normally I'm 88 active and 78 resting. It helper afterwards, but my heart went crazy in the beginning. I was told to stop taking this med. Is this normal?