I'm sorry this happened, this is a tough injury to recover from. That said, I'm going to give you some tough love. Please, for your sake, make your next pair of shoes restaurant-grade. Non-slip and non-permeable for this reason, but very comfortable and usually breath reasonably well.
If there isn't a store in your area,
$1 will ship and exchange until you get one that fits; plus they are much less costly than most specialty shoes.
These sort of burns are precisely why most restaurants, etc. state in their dress code that tennis/sport shoes are strongly discouraged (if not outright banned). Non-slip, too, for what I hope are reasons you don't also learn from experience.