I have gallstones, lately I have this nagging pain on the side of my right rib cage and back can it be the stones?

Fer Sher. The location and description of your pain is likely secondary to gallbladder disease. These attacks typically occur after eating (esp. Fatty foods), last for an hour or more, are assc. W/nausea +/- vomiting, and may radiate into the back. On occasion, chronic obstruction occurs, often leading to constant low-level discomfort. Please see a surgeon.
Yes. Gallstones are known to cause pain in the back on right side which is called reffered pain.