My mother is in complete denial that she has dementia. I cannot get her to the doctors again( I did get her there once) Huge mood swings almost bipolar, tears one day and hysterical laughter a few days alter. Is paranoid about money, thinks everyone is stealing from her ( manually checks shop till receipts) . No memory in short term, always worried about nect meal, losses almost everything, ( so leaves everything out so she can shee it. has started burning food, throws items in temper, shouts at her husband of 40 years. Gets terrible anxious about sugar free food one day (diabetic) and eats chocolate the next! Are we moderate or just at the begginning... I dont know, They both came to live with me 8 months ago
My husband and I discussed his dementia openly and freely. My family has never used the word "dementia" to my mother. Different people need to be approached differently. It sounds like your mother is not one to discuss dementia openly. Don't try to get her to the doctor to see about her dementia! Get her in to renew her tetanus vaccination, or because the insurance wants a baseline checkup or for any reason she might accept. Let the clinic know the true reason for the appointment and that "dementia" should not be mentioned.
Some kinds of dementia do progress in recognizable stages, but others do not. All of the symptoms you mention are very common in dementia, but will occur at different points in different kinds of dementia.
Even if you can find a doctor to tell you "this is stage 4" that won't tell you how long it will last. I do hope you can get her into a doctor and find some ways of treating her current symptoms. Learning how advanced the dementia is may not be as valuable as you hope.
As you know, there is no cure for dementia, but there are drugs that can sometimes help lessen the symptoms. Perhaps an anti-anxiety med would be useful, for example.
Also, how you react to her symptoms can impact her behavior. Learning about dementia and joining a caregiver group can both be helpful in that regard.
Keep us posted. You are in good company here!