Thanks for your query at DoctorSpring.com.
You seem to have developed a rash on your skin near your buttocks. There are a few possibilities for the raised red bumps that could be causing the breakout. This is a common area for heat rash, irritation due to friction, and skin infections (due to the warm moist environment of the skin in that area), and boils or pimples. All of the above mentioned are self-limiting conditions that will usually go away on its own. In the meantime, here is what I suggest for you:
1. Wear loose fitting clothing and underwear to avoid further irritation and inflammation of the skin, even while sleeping at night.
2. Keep the area clean using warm water and mild soap, as harsh soaps and extreme water temperatures can further irritate. Allow the area to air dry on its own without rubbing towels or cloths.
3. Calomine lotion can help if it is itching (as in heat rash or prickly heat) and hydrocortisone creams can help to speed recovery. Be careful when using ointments and creams as you still want the skin to breath and not suffocate beneath the creams. Use only as needed.
You should see regression of the rash in about 1 week. If symptoms persist or if you notice that the rash is getting larger, starts bleeding or scaling, or is spreading to other areas of the body, then these might be signs of a more serious illness or infection. Make an appointment with your local dermatologist in this case as you may need oral medications to assist you in recovery.
Hope this helps, please feel free to discuss further.
Take care and be well.