Two days ago the right side of my neck/shoulder started with a pulse/throbbing pain.what can i cause this?

Nondiagnostic: Try to localize the problem by turning your neck and then moving your shoulder and see what precipitates or aggravates the discomfort. Neck cause could be a pinched nerve; shoulder could be acute tendonitis. Cold or hit applications and NSAIDS like ibuprofen may help. See your Physician if symptoms persist or worsen.

Muscle pain: You may have a spasm of the neck or shoulder muscles. Warm, moist heat may help. Wring out a small towel with water, place in microwave for one minute and apply to affected area. If you are not allergic, take 200-400 mg ibuprofen every 8 hours with food.