Over the last eight years I have treated a number of women who have sustained injuries from wearing ballet flats!
The flats are out and bring in the heels! Quite often a flat shoe can increase pressure at the heel and bend the forefoot in unusual ways. This can contribute heel and forefoot pain.
I commonly recommend a shoe that has a small to medium heel height with some stiffness in the toe box section of the shoe. That is the shoe doesn’t bend excessively when your foot is pushing off.
I recently had the guys from Bared shoewear https://bared.com.au/ come and visit. There are some great options here!