That pulsing sensation in your abdomen is your aorta, the main blood vessel from your heart to your abdomen and legs. The pulsing sensation may not be abnormal. If you are very thin, it is possible to see your belly pulsating as your aorta pulses.
There are some very severe conditions that can cause this as well, such as an aortic aneurysm. Because of the possibility (though small) that this is a severe condition, yo should head to the doctor tomorrow for an in-person physical examination.
Best of luck to you!
Thanks and Happy New Year!
-Dr. Scott W, MD
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