Since you are a weight lifter, the vagus nerve is definitely worth looking into, although you may have a hard time convincing a doctor of that.
Stress can do strange things, and easing it often has profound effects. If you're sure the stress is only due to having these symptoms, and can find no other changes in your life that might account for it, then you can move on to other ideas.
The body's ability to handle certain foods with ease changes as we age. You're only 45 but that's not too young to see this. Having pain immediately while, or just after, eating usually indicates some kind of stomach upset, like gastritis, but the endoscopy should have picked that up. Pain 2-3 hours later could still be in the stomach, but also might be small or large intestine based.
Your doctor may be on the right track suspecting gall bladder issues, but since he put you on Protonix, which is a Proton Pump Inhibitor designed to reduce the production of stomach acid by 90%, he may feel there are other issues. Or, as do most doctors who are just guessing in the early stages of these type of symptoms, he may have just prescribed that as part of the trial and error process of diagnosis.
If you intend to take any PPI for more than a few weeks, you should start taking supplements with calcium, magnesium, potassium, Vit B complex and Vitamin D3, if you are not already doing so; as these are the main essential nutrients that often go unabsorbed properly due to lack of stomach acid.
Until your doctor narrows this down to something more definitive, (and don't be surprised if he/she never does) I would start working on your main symptom, which appears to be gas. The FODMAP diet is an excellent place to start. Followed to the letter, it's extremely restrictive, as it eliminates all gluten and lactose, but it's a good way to find out if certain foods or food groups are causing you problems. Googling FODMAP diet will bring you to dozens of sites with charts and explanations.
Start by following all of its restrictions for about
3 weeks and see if you notice any effect. If it's working, then add back *one* source of gluten for a couple of weeks and see if it still works, then add back another, and another. If still good, then starting adding back sources of lactose, one at a time. Along the way you might discover what foods are the culprit. If it continues to work for you after adding back gluten and lactose, then the rest of the diet is much easier to stay on permanently.
Another way to attack the gas issue is with the Fast Track Digestion books by Norman Robillard. He has a more novel approach, one that doesn't restrict all carbs ( the major source of gas) but only the ones that are the most gas causing. Surprisingly, he has found that some varieties of potatoes cause gas, while others don't. The same with rice. It's an interesting read with scientific testing to back up all his theories, and recipes to help you apply it.
I wish you luck.
Post Edited (rjdriver) : 5/4/2015 8:04:58 PM (GMT-6)