Men can't get PMS, because men do not menstruate. PMS is short for pre-menstrual syndrome.
But, men have hormonal shifts and changes too that can effect their moods, like anyone else.
Having your period has no effect on your metabolism. They are different things in different systems of your body.
Men can pre-ejaculate at any time when they are aroused, so yes, it can certainly (and usually does) happen in those instances. Which is one of the reasons to use a condom DURING those instances.
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