Around my left kidney I get a sudden feeling of extreme heat that lasts for about 10-30 seconds It is not hot to the touch but feels very warm internally sometimes also feel muscle twitching?

There are several potential causes for the symptoms you are experiencing. Here are a few possibilities:

1. Kidney Stones: Kidney stones can cause sudden, intense pain in the flank (area around the kidneys). This pain is known as renal colic and can be accompanied by nausea, vomiting, and sweating. The heat sensation you are feeling could be related to the inflammation and irritation caused by the kidney stones.

2. Urinary Tract Infection (UTI): A UTI can also cause discomfort and pain in the kidney area. UTIs are usually accompanied by frequent urination, burning sensation during urination, and cloudy or foul-smelling urine.

3. Muscle Spasms: Muscle spasms in the back or abdomen can sometimes be felt as heat or twitching sensations. These spasms can be caused by various factors such as dehydration, electrolyte imbalances, or underlying medical conditions.

4. Nerve Issues: Certain nerve problems, such as pinched nerves or nerve damage, can lead to abnormal sensations such as heat or twitching.

5. Other Medical Conditions: In some cases, the symptoms you describe could be indicative of more serious medical conditions, such as a kidney infection, inflammation of the kidney (pyelonephritis), or certain types of cancer.

Given the nature of your symptoms, it is essential that you seek medical attention as soon as possible. Your doctor will be able to conduct a thorough evaluation, including a physical exam, diagnostic tests, and imaging studies, to determine the exact cause of your symptoms and recommend appropriate treatment. Do not delay in seeking medical advice, as certain conditions may require prompt intervention.