Hello,
The symptoms are suggestive of a boil. A boil generally starts as a reddened, tender area. Over time, the area becomes firm and hard. Eventually, the center of the abscess softens and becomes filled with pus. Finally, the pus "forms a head
. Take some over the counter pain reliever and consult a doctor for examination and antibiotics prescription. If there are recurrent boils, then please get her blood sugar levels estimated.