My feet feels hot from the inside but the outside is not too cold or too hot. ?

Neurologist, Primary: Get a Nerve Conduction Velocity test to check your nerves. Also get a diabetic evaluation from your primary care doctor

Hot heels: compression of nerve roots L4,5 and S,1,2 can cause any where from burning, tingling, itching sensation in the feet/heels. that is why it is not hot to the touch. probably happens at night. Apply ice to low back to see if symptoms subside

This may be a : Form of neuropathy you are feeling. You would need to be examined by a doctor.