I'm sorry to hear you're experiencing persistent pain on the right side from the shoulder to the leg, especially when it worsens before your periods. This type of pain could be related to several possible causes, including:

• Hormonal influences: Pain worsening before periods suggests a link to the menstrual cycle, possibly due to conditions like endometriosis or premenstrual syndrome (PMS), which can cause pelvic and referred pain.
• Nerve involvement: Pain radiating from the shoulder down to the leg might indicate nerve irritation or compression, such as sciatica or cervical/thoracic spine issues.
• Musculoskeletal causes: Muscle strain, joint problems, or inflammation in the shoulder, back, or hip could contribute to this pain pattern.
• Gynecological conditions: Disorders like endometriosis or ovarian cysts can cause cyclical pain that intensifies before menstruation.

Given the complexity and the range of possible causes, it is important to consult a gynecologist or a pain specialist. They can perform a thorough evaluation, including physical examination and appropriate imaging or tests, to identify the exact cause and recommend suitable treatment.

If the pain is severe, worsening, or accompanied by other symptoms like weakness, numbness, fever, or difficulty moving, please seek medical attention promptly.To narrow down potential causes, we will need some more information.Could you please provide your age and gender?