What is it when i have a sharp pain on my side?

Need to monitor: A pain in one's side may be caused by various factors, such as a muscle strain or pull, among other possibilities. The character of the pain--onset, frequency, severity, sharp, radiating, changes (or not) with taking a deep breath, in addition to one's other symptoms--needs to be determined to narrow down the possible causes, with further testing based on the most likely possibilities.