Hi, thanks for writing to HCM.
From the given description, I am of the opinion that you have suffered an intercostal muscle
pull or catch making you painful while coughing, breathing or laughing.
The general conservative measures for this condition is as follows -
* avoid lying on the affected side
* Ice packing to relieve the acute pain
* Local application of painkiller gel (as you are intolerant to oral painkillers)
* once the acute pain subsides, moist heat application to relax the soft tissues
Hope this information is helpful. Good day