I feel a tingling sensation in my belly button almost as if im being tickled from the inside. theres no pain but it feels uncomfortable when i stretch. what could it be?

The belly button is where the umbilical cord attaches to the fetus. A structure called the urachus connects the umbilical cord to the developing fetal bladder and acts as a bladder until the baby’s becomes functional. Before birth, the urachus scars over and becomes a ligament that runs from below the belly button to the top of your bladder. Stretching this ligament gives your symptoms.