How to get aging parent to gp

How do I get an aging parent to a gp.

My mother is 70.
Over the past 15 months or so I noticed some things in my mother. There's an issue on speech where she goes in an out from periods of jo conversation and that can go on for weeks at a time. It doesn't make sense to me. There were other stuff and behaviours too and I started tieing them all up together and I think maybe there might be a dementia brewing in her.
I got her to the doctor last summer but there was no progression with any diagnosis.
Her behaviours and temperament has stayed much and the same over the past few months.

Until this weekend. I live at home. But I went out on Saturday for the day and stayed overnight and came home on Sunday. She was in an odd form on Sunday. There was limited conversation from her. I gave her an update on the event and people there and people not there. She did chat along but she was angry and critical of some people so I left it.
A few hours pass and she wasn't talking to me before eventually in a bad tone saying - we need to do that shop. It was in such a bad tone from her.

Then after the shop she told me, don't be telling the siblings about any update about your father. Then she told me a tale.
She said 20 years when X was working abroad, your father told him a whopper of lie about his health being bad and then X got worried and rushed home.
I was old enough to remember 20 years ago and I don't ever remember X rushing home to be with our father.
That never happened.
My mother invented a story to accompany her demand of me.

I accepted her tale and didn't question it but I know in my heart and soul that it's not true.

Then yesterday morning I got up and she was in a bad mood all morning and she was angry. Her anger was silent though. You could cut the tension with a knife.
She did ask me a question about work but then she decided she wanted a walk and I will have to stay at home to take in the shop instead of going to work because her walk was more important.
She was just in such a bad mood. She was angry.

That angry tone has continued into today.
She took out the washing dispenser drawer and started washing that while barking at me to search online for a washing machine cleaner and what's the best cleaner. She said the washing machine was being loud earlier and she needs to clean it. But I was in the kitchen when the machine was on and it wasn't loud.
It was a normal spin. I replied saying I will search online.
About 10 minutes later, I replied to her saying vinegar is a good cleaner in a wash.
She just barked at me.
Not as in a 'woof, woof' way. She was just angry.
I asked her if she needed a hand to put the dispenser back into the machine and she got mad at me once more. I don't know if she remembered asking me about the washing machine 10 minutes prior if if she understands what I am saying to her and maybe her reaction is anger.


None of this is right. I had suspicions for a long time maybe there was something happening like the possibility of a dementia and I think maybe there's something happening.
Or maybe even possibly a uti but it's not showing as typical symptoms and it's showing itself up as anger.

So I am concerned that there's something happening with her. I don't know what though. If it's a dementia or something like a uti that's showing in a strange way.

She's a stubborn person though.
I would never be able to be open with her and ask her to attend to her GP in case it's a uti.
All that will do is result in a rage.
Or will I ignore this until if and when it progresses?