Rhabdomyolysis

Hello i am a 15 year old runner who just completed his first marathon. I was very well trained for the event, completeing 80 mile weeks for months before th eevent. Before the event i superhydrated and loaded up on carbs. At around mile 13 i started to have severe stomach discomfort followed by bloody urine and stool. I finished the last 13.2 miles, bleeding all the way and then was admitted to the hospital. They told me my CPK rate was 15,000 and i know the normal rate is around 150. My question is why would my CPK rate raise so high so fast being that i was well trained? How can this sudden rise affect my kidney's and my heart?