I've been having spontaneous heat on my right foot for about 5 months now. i don't think i have diabetes, and i didn't injure myself. what can it be?

Neuroma: Two things it could be: neuroma is an inflammation of the foot nerve that can cause numbness and tingling. It's usually caused by wearing tight shoes for a long period of time the nerve between the metatarsal heads gets irritated then a neuroma occurs. Due to inflammation, it's possible to get warmth. The other is gout from eating too many purines. See your podiatrist about both. Check uric acid.

Possible neuropathy: Neuropathy can happen as a result of trauma, or nerve damage due to the consumption of alcohol or certain medications. Symptoms can range from a numbness and tingling sensation, possibly a burning sensation, to an uncomfortable painful sensation of the extremities. Get evaluated by a professional to determine the exact cause in order to get the appropriate treatment.