My breast oncologist recently suggested Verzenio which is a "twin" to Kisqali (as per her information).
I am on Exemestane (my 3rd aromatase inhibitor, suffering severe headaches from the AIs, my only treatment post BM) and she wants to add Verzenio to "cover all my bases". I am thinking about it but want another opinion first. This medication, like yours, has some serious side effects so my sense is you are not imagining anything!
To me, she mentioned low white blood counts (suspectable to infections), low red blood counts (anemia, fatigue, brain fog) plus severe diarrhea. No question there are lots more. She is really pushing this medication on me.
I have no further info for you but I believe I can safely say everything you are feeling IS a side effect of Kisqali.
All the best to you!