Epididymitis: This condition, which is an inflammation of the epididymis (a tube at the back of the testicle that stores and carries sperm), can cause a dull ache in the testicles. The pain can sometimes be relieved with ejaculation, as it helps to reduce the pressure in the epididymis.

Prostatitis: Inflammation of the prostate gland can cause pain in the testicles, which may be relieved by ejaculation. This is because ejaculation can help reduce prostate congestion.
Varicocele: An enlargement of the veins within the scrotum, similar to varicose veins, can cause a dull ache in the testicles. While less directly related to ejaculation, the discomfort can vary with physical activity and position.
Orchitis: Inflammation of one or both testicles, usually caused by bacterial or viral infections, can lead to testicular pain. The relationship with ejaculation is less consistent but can be considered in the broader context of testicular pain.

Testicular Torsion: Although this condition typically presents with sudden, severe pain, it's crucial not to miss it due to its emergency nature. Testicular torsion requires immediate medical attention to save the affected testicle.
Testicular Cancer: While testicular cancer more commonly presents with a painless testicular mass, it can occasionally cause pain. Given its potential severity and the importance of early detection, it should not be overlooked.

Spermatocele: A spermatocele is a benign cystic accumulation of sperm that arises from the head of the epididymis. It can cause discomfort or pain in the testicle, which might be relieved by ejaculation, though this is less common.
Henoch-Schönlein Purpura (HSP): A form of vasculitis that can affect various parts of the body, including the testicles, leading to pain. It's more commonly associated with skin, joint, and gastrointestinal symptoms but can rarely present with testicular involvement.