Period Hell

Does anyone else out there find they get severe diahorea around ovulation and AF. I find 2-3 days beforehand I get bad bouts of it to the point where I'm too afraid to do anything as I've had to many close calls. I've always had a very sensitive stomach and always feel sick most days but this is getting ridiculous. Had tests done and nothing shows up plus don't have any food reactions. I do have PCOS so not sure if this is causing it 😡🤢💩