It could well be diabetic neuropathy. When did you last have them checked as part of your diabetes care checks? If your nurse/doctor is not aware of this problem, you need to make an appointment. You need a proper diagnosis, which we aren't able to give you.
Please be very careful. What you don't want to happen is to go barefoot, even in the house, as you need to avoid any cuts. Wear thick socks and sensible shoes. If you tread on something you won't be able to feel it, and this can turn very nasty.