Thank you for the additional information-
The stitch like pain, pain radiating to the back and right shoulder blade along with the nausea could be gallbladder related. Usually, if there is any type of pain in the abdomen radiating to the shoulder blade, it can be a sign of irritation of the diaphragm (gallbladder being one of the more common causes) so I would recommend that you follow up with your doctor to check this out.
The stitch could also be a sign of muscle cramping in between the rib or pleurisy
which is usually due to a viral
infection of the lining of the lungs
. This causes a sharp pain that is worse with deep breathing. Treatment for this condition is anti-inflammatories such as ibuprofen. I would still recommend that your doctor diagnose this though.
I would not expect simple heartburn to cause pain on the right side of your abdomen or under the right side of the ribs. Typically, it will cause some pain in the left or center of the upper abdomen, radiating into the chest. While it sounds like you are also having heartburn, I do not think it is solely responsible for all of your symptoms. You can try taking over the counter omeprazole or zantac for the heartburn symptoms.
So, to sum up, I would see your doctor for evaluation of the right sided pain. It may be gallbladder related, pleuritic pain (inflammation due to a virus) or muscle spasms, to name a few causes.
I hope this is helpful information for you. If you have any other questions or would like to discuss further, let me know.