I was playing tennis yesterday and I had to stop because I hurt my back while serving. It hurts during the follow through, it's kind of in the middle right side of my back. This is the first time I've ever hurt it playing tennis, has anyone ever experienced this? I'm a right hander and basically I'm following through on my serve I feel discomfort in a muscle on my back. It's strange because this is the first time I've ever experienced this kind of back pain while serving; the back pain I've experienced before was lower back pain right in the middle of the back.