I am currently a high school student, and am involved in a very rigorous marching band program. Last week, we were working on choreography for our field show. While practicing a particular move, where we throw our arms out, my left elbow "cracked," and I felt a surge of pain travel up throughout my arm. Ever since then, my left hand has been shaking at random, and it has become increasingly harder to carry heavy objects. Is there anything that may be cause of this?