Hi!
I'm my dad's carer! Every single person with dementia or suspected dementia will progress differently..The only certainty is that dementia is progressive...my dad has dementia with let bodies which has symptoms of alzheimers and parkinsonism. This mean his gait and mobility is stiff shuffling and he falls as his balance is appaulling. I checked hearing and sight etc to make sure they weren't causing balance issues etc.
Other illnesses falls infections where their dementia is at can all determine the progression your noticing.
Make sure you ask and accept help and look after yourself too!
Best wishes