I have the same thing exactly …my mood is often ok but inside I can feel the anxiety …. For me it tends to manifest in stomach so butterflies, not wanting to eat etc. Also shaking, sweating etc. not much seems to help. Usually worse in morning and wears off by evening.
I am just finishing four months of CBT, basically there’s not much you can do to stop the anxiety (which is obviously physical in case of peri and menopause) but it’s a matter of looking at it, seeing there’s no real cause and then just trying to move on with your day despite it. CBT has been useful for strategies to stop that physical anxiety spiralling into negative thoughts, stop it changing your behaviour (like avoiding things or situations for example).
But yes it’s so miserable!