The most everyday cause of this is acid reflux from the stomach.
For that I'd encourage you to really take time to relax and enjoy mealtime, chew for longer, eat little and often and if necessary, take a digestive bitter such as Centaurium before eating as it will help the acid reflux.
However, if the pain is over your right shoulder blade and into the right side of the neck, you may have to consider asking the Doctor to check for gallstones.
Unfortunately, I can't recommend anything while there is a possibility of gallstones as we don't want them to start moving but if the doctor gives you the all clear and you can say that the pain comes on after eating richer of fattier food, or is aggravated by bacon, wheat or onions, please consider a product called Digestisan, which helps gallbladder and liver function.
This is all assuming that you haven't simply wrenched your shoulder of course. In that case, Arnica Gel and rest are the best remedies.
Hope one of these strikes a note with you.