I hope she is ok. But if not then you have my deepest sympathy, I went through this with my Mum.
I took Mum to a memory clinic to be seen by a Psychologist dealing with older people's issues. Do you have anything like that over there? She would get a diagnosis and possibly some medication.
Unfortunately the progression of dementia can't be stopped, but it can be slowed down to an extent.
Of course that's assuming your Mum is willing to go to such an appointment.