About a month ago i believe i might of hyperextended my elbow throwing a ball. A month later the pain is still there. When I have someone stretch my elbow by laying my forearm back and start at about 120 degrees there is no pain, but once they bring it in to about 90 degrees i feel pain right under the elbow close to the inside of the elbow and a little above the elbow in my forearm. Once they let go of my arm quickly and it bounce back up i feel enormous amount of pain. Its kind of in my forearm right above my elbow. Its like my bones were bending and now they are going back in place. Anyone one have any idea whats wrong? Trainer says it is tendinitis. But can tendinitis happen with just one throw. Also when I initially hurt my arm there was black and blue brusing where it still hurts, right under the elbow on the inside, part of the tricep where there is a muscle that pops up right before you feel the elbow bone, the pointy part.