Don’t worry - as others have said the CAA will not take further action beyond possibly writing to you.
You decided that the failure could have been indicative of something more serious.
Given that was so, a diversion was in order.
Aviate, navigate, communicate - forget all that old tosh.
It may work went you are mid channel or in some desolate and remote region of the UK but not surrounded by busy CAS.
The effect of the words “I have a small problem” is amazing if you are reluctant to call a pan.
Of course ensure you have the problem under control, but if you are “panicking” even a bit a cool head on the ground is worth its weight in gold. Immediately, they are expecting you to do something “stupid” like divert through CAS without thinking about a clearance because it just happens to be the shortest route. Moreover it gives them something a bit more interesting to do for the day.
It may be decried by some but it is much easier to have someone helping with the navigation with a 20"screen in front of them whilst you are managing the problem.