Hello,
From the
symptoms it sounds like a boil or an abscess. A boil caused due to
staph infection 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," which can be surgically opened or spontaneously drain out.
Apply warm compresses on these bumps and consult a dermatologist for examination and confirmation of diagnosis.