answer:Just guessing. I am not a medical professional and I have never heard of this before. It sounds like it could be nerve pain. When you sneezing the morning are you laying down? As opposed to sitting or standing up during the day? Maybe your position is aggravating or putting pressure on a nerve. It also could be in the morning having slept in a certain position your muscles are creating some sort of stress on a nerve, but through the day it is relieved. Since pain down the arm is a classic heart attack symptom, maybe you are having a moment of some sort of something that creates that same discomfort as when blood is not flowing correctly throught the heart. I doubt it is something dangerous, but I do think it is good to check with your doctor just in case. If he thinks it is heart related he could order a heart monitor to wear overnight so you can record during your sneezing. But, honestly, I have no idea if that is really a concern. I really think it is a nerve in the spine, changing position or controlling your neck and head position when sneezing might be the cure. Another idea is to take ibuprofen for a few days if this is a new thing. Possible muscles are inflamed and pinching on a nerve and reducing the inflammation will cure the problem. Do you lift heavy things during the day? Have any history of disc problems, or neck and shoulder pain and tension? Let us know what the doctor says.