Pain running up neck to underneath ear,swelling momentarily then disappearing after 5-6 seconds...

Muscle Contractions?: Possibly muscle contractions in the your neck. See your doctor for a checkup.

Need to examine: It is not feasible to provide a meaningful opinion without examining you. If the symptoms persist for more than two weeks, or get worse, see a doctor. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex, if you have sex.

Needs examination: Variety of possibilities including muscle spasm/referred pain from spinal or ligamentous structures to referred pain from ear or throat or other medical problem affecting neck or glands. Best to be seen by a doctor in person to get further details and examine you physically +/- arrange tests and treatment if needed. All the best.