Thanks for your query
Your baby had hematoma
formation at injury
site due to rupture of small blood vessels.
Apply ice cold
compresses over affected area for 5 to 10 minutes 2 to 3 times a day.
Give acataminophen for pain relief.
Watch for any lethargy/vomiting
.bleeding from ear or nose.
In case you observe any feature take her to ER for further management.
Wishing your baby good health.