Hi toffeecushion,
Yep, I'm the same as Sparkle and Machair: it's the hormone fluctuations that cause this and it can apparently continue for a few years post meno. In peri all can be chaotic with the ovaries and pituitary gland utterly determined to maintain a cycle thus the pmt type symptoms with no bleed. I've found that this has calmed as my last few bleeds have been anovulatory. To be honest I've given up expecting these pesky periods to ever end, I'm just going with the flow now (no pun intended!).