My Son Got Severely Dehydrated At A Football Camp Last

my son got severely dehydrated at a football camp last Thursday, we took him to the er and they gave him 2 bags of fluids and sent him home. Saturday we went back to the er because he was having sever abd pain, they gave him 2 more bags of fluid and said the abd pain was from the dehydration. Monday night we ended up back in the er because of the pain and they did a CT abd they said it was normal and all the blood work they did was normal. They still said it was from the dehydration. Wednesday morning he was still having issues his family DR. order and ultrasound of his abd which came back normal. Wednesday night we ended up back in the er with severe abd pain they ran more blood work and said they are now leaning toward it being muscular. Thursday they started him on muscle relaxer he is still hurting any suggestions on what else we need to be doing?