slow heart rate during period

Maria
So every so often when it gets close to that time of the month I wake up feeling about "normal" cramp pains but then as the day progresses it comes to a point where my whole body feels weak, I begin shaking, I get hot and sweat cold, I vomit, feel like I'm about to faint, and bleed exesively. This time around I was able to check my heart rate and it was at 50 beats a minute! Is this normal? And if anyone has ever felt similar symptoms what did you do to help make it go away besides drinking Camille tea and taking Mydol?