I have a pulsing sensation on the left side of my belly button. it's not constant and could be described as a tiny baby kick! what could this be?

Fasciculations: Twitching, which is an abnormal firing of muscles, is the common term for fasciculations. The sensation of your abdomen twitching can be very annoying but no cause for alarm or fear. It could be the result of anxiety, stress, dehydration and/or mineral imbalance. Make sure you are getting enough fluids and adequate amounts of magnesium and potassium.