What can cause my right breast to hurt even though there are no lumps?

Probably fibrocystic: Breast pain and lump are not always present together. Most of the time breast pain is secondary to fibrocystic condition, breast cysts, inflammation or breast infection. Some cancers are also painful. If your symptoms are new, it would be advisable to have a clinical breast evaluation to determine the cause of the pain. Breast lump and pain whether together or not need to be checked medically.

Fibrocystic changes: Could be fibrocystic changes, a cyst, or an infection. Always best to see your physician to report any changes in your breast.