I have been diagnosed with walking pneumonia, i've been prescribe a strong antibiotic for 10 days. my chest is feeling bruised pain on the right side & back. is this one of the situation where the codine cough medicine would help?

Codeine is no longer used/ recommended for pain, rarely used for severe cough, talk to your doc about your symptoms, abstain from self treating.

Codeine cough syrup is primarily prescribed for relief of persistent dry hacking cough which can cause rib cage discomfort. Notify your MD if chest pain becomes worse and/or breathing difficulties develop or if chest pain on deep breathing occurs as this could indicate pleurisy with development of fluid buildup in the chest cavity.