Ejaculatory pain. Ejaculation occurs with the spasm of a series of tubes that lead from the testicles to the prostate/seminal vesicles and out of the urethra. These vigorous spasms can lead to occasional discomfort, especially if there is reflux of the seminal fluid backward into the epididymis. Some dull discomfort is not worrisome. Burning, pain, and fever could indicate infection, which should be evaluated.