Sorry I thought I'd mentioned it. It's my big toe.
I know web diagnosis isn't the best thing but I was thinking that shims/wedges might be a quick and cheap thing to check whilst I get churned through the wheels of the NHS. It happens the most in road SPD shoes (with Look Keos), less with MTB SPD and not really at all with normal shoes/trainers on flat pedals though now I've picked up on it I am aware of pushing with that part.
You're very right about visiting the professionals as to add to the mix I'm diabetic so I have to be extra careful with my pinkies.
Thank you,
Pete