Getting hard refers to erection. Penile pain after erection may be associated with conditions such as indulgence, urethritis, and urethral stones. 1. Indulgence: If the patient has recently indulged in sexual intercourse, it may lead to genital damage. Penile congestion after erection may induce pain. 2. Urethritis: due to various reasons, bacteria, viruses, mycoplasma, chlamydia and other pathogenic microorganisms invade the urethra, inducing inflammation, which can lead to urethral mucosa congestion and edema. During erection, penile congestion will aggravate the urethral mucosal congestion and edema, and pain will occur. At the same time, there can be frequent urination, urinary urgency and other symptoms. 3. Urethral calculi: Most of the stones from the bladder enter the urethra, leading to urethral calculi lesions. After erection, it can induce the occurrence of penile pain. There are many other reasons for penile pain after erection, such as penile sclerosis, trauma, prostatitis, etc., please consult a regular hospital in time.