There are a number of conditions that can cause pain that is felt in the buttocks. Most of these are not serious, but some do require medical evaluation. The doctors who will be well qualified to discuss this issue with you will include your primary care doctor
or your sports medicine doctor
Several serious conditions, such as degenerative arthritis or loss of bone in the hip socket, can cause hip pain. These are rare in a young person who is not taking medications, who does not have any other medical problems, or who has pain but no limitation in the hip's mobility.
Another serious problem could be an infection of the hip joint. This can be caused by any bacteria, but in young sexually active people is most commonly caused by gonorrhea. If there is fever or a skin rash, this problem may be more likely.
Less concerning, and more common, can be simple inflammation or strain injuries involving one of the joints in the buttocks, the sacroiliac joint, or one of the fluid-filled sacs close to the hip join, called trochanteric bursitis.
As always, the diagnosis and management of your specific condition will require a physical examination by your personal physician. Scheduling an appointment with your primary care doctor or sports medicine doctor is highly recommended if the pain persists.