Would tingling caused by diabetic neuropathy be like a constant thing that starts in one area then continues to spread? or would it be something that comes and goes?

Symptom intensity of a peripheral neuropathy can wax and wan, depending upon emotional state, varying states of alertness, influence of medications. Nonetheless, the neuropathy itself does not "come and go". If there is a question of a diabetic neuropathy, or peculiar fluctuating symptoms, have a neurology consult. Your endocrinologist should also be able to help.