What Is The Cause Of Diarrhea And Stomach Cramps Accompanied By My Periods?

I ve had diarrhea now for at least 6 days and still on-going. I ve also had stomache cramps for about the same length of time too. I came on my period Sunday. Which I thought that s what the stomache cramps resulted to. But I ve never had them this bad before. The stomache cramps have had me to the floor in absolute agony. I ve also been having heart burn and feeling ever so sick and faint, but never actually done so. Before all of this, I have had a water infection. Which lasted for about 10. Then the diarrhea started. Is this normal? Not sure why all this is happening. Do you have any idea? (I am going through a lot of stress at the moment too, if that helps in any way?) Kind regards, Louise.