My child's ear is swollen tierce it's normal size. there is a large swollen area on her head behind her ear. it is warm. what is going on?

Swollen ear: Your child could have an infected ear. The area behind her ear is a swollen lymph node. You take your child to the ER or your doctor

It sounds like an infection.: It specifically sounds like a sebaceous cyst abscess which the child should be seen for. Usually antibiotics will help. Sometimes it requires incision and drainage of the large lump.