I had a buddy that sniffed out our female friend's periods.
It was all *sniff* *sniff* "Are you girls...?"
And then they'd be like "YES ******** OFF"
It was actually a useful super power, he let us know when no to piss them off.
No, I don't notice any body changes before.
But I've been writing down my periods on the calendar for years, and I'm very regular.
So now I know the exact day I'm going to get it every month.