Welcome. A hematoma is a collection of blood within a specific area of the body usually the result of trauma such as your fall by the pool. In your case, the gluteal area has a large bump that has not resolved is probably a hematoma.
The body will reabsorb the blood and can be assisted with heat and gentle exercise. It is important to watch for numbness in the leg, increasing local pain or pain down the leg or up the back. Since the gluteal muscle is contained within fascia, you could suffer from compartment syndrome which may compress nerves in the gluteal area (sciatic nerve). Also, calcification build up can occur and cause a permanent hard nodule in the muscle.
Sometime physical therapy can help resolve some the swelling, pain, and any loss of motion. Icing the area, using a heating pad and alternating these may be of benefit.
Since you are having pain and tingling (which could be nerve related) and it is ongoing, it would be best to see a doctor. I'd do so sooner rather than later. Let us know what the doctor says.
Let us know how it goes or if you have any further questions. Take care.
Hello~I suggest seeing your GP since it is hurting and burning, it is always good to have matters like these looked in to.