Up until perimenopause my PMS always followed the same pattern. Irrational bad temper, irritability, gorging on chocolate, tearfulness and feeling like I was about to shatter into a thousand pieces. Boobs would be swollen and achy and stomach bloated. Then the minute my period began I would feel it all seep away, I would get a short but sharp headache, bit of diarrhoea then would feel as right as rain again.
Since Perimenopause my PMS started the moment ovulation ended. No more irritability or bad temper. Instead a very low mood, feeling life was pointless and a deadening of any enjoyment in anything. It lasted right through until about day 5-6 of my cycle, so some months I only had about 7-10 days of normality. But I stopped havung the bloating or painful boobs. In contrast, when I ovulated I felt almost stoned and felt excessively chilled out and blissful for a day or two.