Woa, there big fella. Hopefully your coach knows about pitching and can discern arm ailments. Firt of all if a kid tells me his arm is hurting, I don't force them to pitch, and if any coach did....that is crazy.
Bicep soreness is no big deal, forearm soreness is no big deal, Lat muscle soreness is no big deal...
Back of elbow (MUEY MALE) Back of shoulder, front of sholder (Very Bad)
There is an annual multi-page thread about paying $50 to go to a tryout. I'd love to a) see what the cost would be for this "solution", b) see the thread on that cost.