Hi CG, you description is a perfect like for like of what occured with my mum.
She was finally taken off them when she had what I can only describe as a funny turn.
She awoke one morning dizy, sick, angry, frustrated, weak.......the list could go on.
Called out doctor, he found nothing wrong, put it down to the tablets, got in touch with consultant and cut long story short, she is now on aricept.
Looking back the mood swing was almost immediate but when we reported it to the doctors, we were advised to give the drug a few more days/weeks.
Obviously, this is just MY story. Hope this helps. Best wishes HC