This is what I found about GERD. Nothing mentions abdominal pain or rib cage pain. Maybe it's just gas pain you are experiencing. I'm not sure. But this is what I found about GERD for you. Hope this helped you a little :)
Michael F. Picco, M.D., MayoClinic
Acid reflux and gastroesophageal reflux disease (GERD) are closely related, but the terms aren't necessarily interchangeable.
Acid reflux is the backward flow of stomach acid into the esophagus
What Are the Symptoms of GERD?
Chronic acid reflux leads to uncomplicated GERD, but not everyone with GERD has heartburn. The primary symptoms of GERD are heartburn, regurgitation, and nausea.
Heartburn usually is described as a burning pain in the middle of the chest. It may start high in the abdomen or may extend up into the neck. Sometimes the pain may be sharp or pressure-like, rather than burning. Such pain can mimic heart pain (angina). In other patients, the pain may extend to the back. Typically heartburn related to GERD is seen more commonly after a meal. Other symptoms of GERD include:
Recommended Related to Heartburn/GERD
Severe Heartburn? It May Be GERD
Hoarseness. If acid reflux gets past the upper esophageal sphincter, it can enter the throat (pharynx) and even the voice box (larynx), causing hoarseness or a sore throat.
Laryngitis
Nausea
Sore throat
Chronic dry cough, especially at night. GERD is a common cause of unexplained coughing. It is not clear how cough is caused or aggravated by GERD.
Asthma. Some of these nerves that are stimulated by the refluxed acid stimulate the nerves to the lungs, which then can cause the smaller breathing tubes to narrow, resulting in an attack of asthma.
Feeling as if there is a lump in your throat
Bad breath
Earaches
Chest pain/discomfort