Hi , I Have A 17 Yr Old Son Having

hi , I have a 17 yr old son having abdominal pains and headaches and fatigue also he aid his kness were hurting and his testicles were alittle sore. he just had an colonoscopy and an endoscopy done came out clean
but yesterday when I saw I'm he said he still had headaches. what do I do? I don't understand with the test came out clean, but his family doctor said his liver enzymes was just a tad high. what can I do for him?