You have not mentioned about the mode of injury
Look for Forceful vomiting/ Bleeding through ears, nose/ Black discoloration around eyes/ Fits.
If none of the above is seen, you need not panic.
The crying might be due to pain.
- Try to give her Acetaminophen
in a dose of 15 mg/kg/dose every 6 hours for a day or two.
- Give cold
compresses with ice over the lump.
If she is still irritable, do not hesitate to visit your Pediatrician
Hope my answer helps you.