You are using too much weight for your current level of strength. I can almost guarantee your form is bad, and you are using everything to get the weight going up with momentum. End result too much stress on the forearms.
Nearly everyone is guilty of training like this at some stage of their life, usually the early part(I certainly was, resulted in acute, chronic joint pain). If you want to get stronger, and stay injury free, you don't need to train anywhere near your personal max. If you want to test how strong you currently are or are in a weightlifting meet by all means go for it.
What most of the magazines and videos don't tell show you are the lifters putting in the time with technique, with manageable weights, really owning it.
I can remember seeing footage a good amateur female Olympic lifters training effortlessly lifting weights in snatch, that you would never think was possible just by looking at them. No grunting, grimacing.
Smooth technique, controlled negatives on bodybuilding/powerlifting exercise, allows you to develop true strength, which you can demonstrate in max lifts when the time is right.