Dear L., I am a grandmother and massage therapist, with grown children in the medical field ..... go to the doctor tomorrow. Do not let him tell you that this is normal. Always listen to your child and be their advocate. Start doing research yourself so that you will have questions to ask. Ask your child questions and make notes of your observations. Write down your questions. Ask your mother, and mother-in-law. (has anyone in the family ever had something like this?) Always go to the Dr. with paper in hand. have your questions written down, with space to take notes on each one. Take a friend or your mother with you, two brains and two sets of ears are better than one. Don't quit till you are satisfied with the answers you get.
My eldest began to exhibit symptoms at 7 yrs of age that was finally diagnosed at age 11 with juvenile rhuematoid arthritis. We were dismissed with comments of 'she just can't handle growing pains', 'she wants to get out of school', 'you are a hypochondriac mom, transferring to your child' .......... but she was in pain. I kept a diary of symptoms, what she ate (was there a connection), seasons, activities, anything that I suspected of having a connection. And we kept repeating tests, requesting new ones (it shocked me to find that most tests only have a 50% reliability)
After she was diagnosed I continued my efforts because I knew the affects of the cortico-steroids they put her on (they take calcium from the body, and impede the immune system). Becoming a vegetarian (her choice, she's still a vegetarian in her 30's) alleviated her symptoms enough that she took herself off the meds.
So start your journey, and don't let anyone shrug you off or dismiss these symptoms. But don't be too fast too give him meds. Could be a change in diet is the answer. Investigate food combining. But make sure there isn't something physical; a hernia, an ulcer (stomach is higher than most realize), lung issues, heart issues......
Keep us posted.