Some women experience abdominal tenderness or point tenderness in their abdomen during pregnancy. Abdominal tenderness refers to the pressure experienced on an area of your abdomen that causes pain and this makes the belly button sore.

sometimes the removal of pressure causes pain on the belly button, the pressure felt is known as rebound tenderness or Blumberg sign. The Point tenderness may indicate that something is wrong with one or more organs in the area.

Abdominal tenderness might be caused by an inflammation or other acute processes in one or more organs. A sharp pain when the belly button is pressed may  mean sudden pressure caused by something
Some common causes of abdominal tenderness are:

appendicitis: appendicitis occurs when the appendix (a small pouch that is attached to the small intestines) is blocked by the waste products (feces) traveling through the intestines.

abdominal abscess: abdominal abscess occurs due to an infected fluid or pus that forms a pocket inside the belly. The main cause of an abdominal abscess is; a burst in the appendix, intestine, or ovary;  and sometimes inflammatory bowel disease (IBD); or infection.

Meckel’s diverticulum: this refers to a small bulge that appears on the small intestines. this remnant of the umbilical cord can cause bleeding and or internal obstruction later in life. 

Common causes for women include:
inguinal hernia:  inguinal;l hernia refers to a condition that through a weak spot thus causing increased pressure on the belly button. Studies show that hernia is due to excess pressure near the belly button that in return causes the intestine or sometimes the fat tissues to bulge out on the marvel. The only way to treat a hernia is by surgery.

however, you should look out for these symptoms, vomiting that is associated with sharp pain. If you happen to experience this seek medical attention immediately

people who have hernias also experience tenderness on the belly button when touched or stretched. Also, inflammatory bowel disease can cause pain near the belly button due to the affected small intestines.
Be alert to call your doctor if your symptoms seem to increase or worsen this can point to Crohn’s disease.

twisted fallopian tube: this refers to a rare condition in which one or both fallopian tubes twist on the tissues that surround them
ruptured ovarian cyst: sometimes cysts form on the ovaries where follicles form. these cysts may burst causing pain when one stretches
ruptured ectopic pregnancy: this is a life-threatening pregnancy condition. This condition occurs due to the bursting of the fluid holding the fetus in the uterus.

pelvic inflammatory disease (PID): refers to an infection of a woman’s reproductive organs. Often forms due to the complication of several kinds of STDs, such as chlamydia and gonorrhea. All these symptoms cause inflammation. Inflammation leads to swelling that causes pressure to form inside the abdomen resulting in tenderness.

conclusion
being aware of the cause of your belly button pain helps you find the treatment that suits your pain or discomfort. Sometimes the pain may start at your belly button, and migrate to other parts of your stomach. Ensure you are keeping track of all the symptoms you experience to help your doctor  find the cause and treatment quickly