i have left side breast nipple pain and a small...

Treatment of breast pain:
It depends on the cause, so treatment ma include conservative management as hot compressors or you may need analgesia as ibuprofen 400 mg twice daily and diclofene cream twice daily for muscular pain and you may need antibiotic as augmentin 500 mg three times daily for infection or surgery as for abscess, tumors

Diagnosis of the cause of breast pain:
You have to visit a surgeon for clinical examination and investigations as CBC, ESR, CRP for infection and breast US or CT scan
Causes of breast pain:
It may be due to:

• Muscular pain which increase with movement and respiration
• Infection which associated with redness, swelling and hotness
• Tumors which associated with mass, loss of weight, inpple retraction.