Do I need to get umbilical hernia repaired?

How big it is ? Most of the adult umbilical hernia with a defect size of tip of the finger do not bother and can be left alone. How ever larger hernias over 2cm or more, will potentially will give complications, pain, incarceration, obstruction, gangrene of bowel, peritonitis etc need as soon as possible surgery to prevent complications.
If you have pain. The most common reason that an umbilical hernia would need to be fixed is that the patient is bothered by pain and sometimes a bulge at the hernia site. Large hernias usually should be fixed. Umbilical hernias need to be fixed immediately if intestines are stuck within them (incarcerated), especially if the blood supply is cut off (strangulated), but this is quite rare.
Likely . If you can see it and it or it bothers you then yes.