I have PCOS so for decades I didn't have proper periods, and also didn't have PMS. Since I started taking Metformin I have had fairly regular periods.
At the start the PMS was a sort of uncomfortable clarity about my life. The rest of the month was a daze of dealing with immediate day-to-day things and thoughts about the future were vague and happy (eg when the DC are grown I will travel to X, or take up Y hobby) and the PMS day (usually just one day) was like putting on the correct prescription glasses and seeing that the future is not necessarily going to be all fun and laughter.
The last few months have been slightly tougher going, I'm still generally happy but there are things I should be addressing (like relationship issues) that I'm putting off. However on PMS days I just feel as though I'm drowning under waves of despair. I know it won't last long so I take things easy, get rest and am just generally nice to myself, and do my best not to be too snappy with everyone else, but I'm often on the verge of bursting into tears. I haven't felt like this since I was having IVF and was pumped full of hormones that made me very moody.
TIA