There is reason for concern, but no need to panic. First and foremost, clean the wound extensively with soap and water, apply an antibiotic ointment, and cover with a Band-Aid. A visit to the pediatrician should be your next stop.
The doctor will likely prescribe a broad-spectrum oral antibiotic to cover against infection. Be on the lookout for signs of redness or swelling in the area, which may indicate a spreading infection.
You also need to consider whether your child is completely vaccinated against tetanus. If she is up-to-date on her vaccines, you are in the clear. If she is behind or you have elected not to immunize your child for some reason, know that she is at risk for developing tetanus, a life-threatening infection. Talk to the pediatrician about a special shot to protect your child since she may have been exposed.