I am wondering if you can give me any insight into why I am experiencing these symptoms: all on the left side of my body; shoulder, elbow, arm, groin, and leg pain. Thanks!

Imbalance. When the body is too asymmetrical, you may suffer pain all over that side of the body. Not having examined you, the first thing you need to find out is whether one of your legs is way shorter than the other. Another aspect to consider is that when one of joints is inflamed, one's posture is also changed and in turn may lead to pain to the rest of the joints on that side of the body.