It can be due to folliculitis or boil. Do not use any cosmetic products at the sites. You can apply some calamine lotion at the rash as it will help in soothing the skin. Also wear cotton clothes. Application of mild corticosteroid cream prescribed by your doctor and oral antiinflammatories like ibuprofen/acetaminophen are also helpful. Topical antibiotics such as mupirocin or neomycin containing ointment are also useful on the bump. If the symptoms are severe then it will be best to consult a dermatologist.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
I think it's a harmless ingrown hair or other blocked pore issue.