Hi.
You are clearly not 'dim', as you other results indicate, in general. So there is nothing to worry about.
With that Maths grade then you would struggle too much to cope with advanced Physics. BUT why are your Maths grades so low? Rather than just chucking in the towel, I would suggest that you could try an alternative approach. It can be easy, in School, to get on a slippery slope once you and your teachers have decided you can't do Maths. Consider some private Maths tuition with someone not associated with your regular School and who, perhaps, is a bit 'different'. This may get you kick started. Even a book might help. When students used to ask me what book to buy, for extra Physics information, I used to tell them to go to the shop (library) and browse. If the presentation of a particular book takes their fancy, then go for it. (The Maths /Physics/ whatever, is very unlikely to be actually Wrong in a textbook)
If that fails you then go for something other than Physics. You could clearly make a success in another direction. There is absolutely no shame in that. I have many friends who are completely Durrr about Physics but who are clearly a lot more intelligent and able than I am.
I could even suggest that, as your present maths is at a lowish level, then you may not even be appreciating exactly what this 'Physics business' is. You may not even be really sure of what it is that you feel you are in love with at the moment. There are plenty more fish in the sea.