A bump on your forehead, even if it's small and doesn't hurt, can still be cause for concern. Swelling under the skin (called a hematoma or “goose egg”) is usually a temporary symptom of head trauma.

How long does it take for a goose egg to go away?

If it doesn't stop bleeding after a few minutes, seek medical attention. Once clean and dry, apply a thin layer of antibiotic ointment and keep it covered with a bandage or gauze. Change the dressing once or twice a day until it heals — typically about seven to 10 days.

How serious is a goose egg?

If your child develops a “goose egg” — an oval protrusion — don't worry about it. “It's just a swelling of the scalp caused by trauma to the skin and broken blood vessels,” explains Dr. Powell. It might take a while to go away, but it's nothing to worry about.