Really, until proven otherwise, this sounds like a heart problem. However, if that's definitively been ruled out to your doctor's and your satisfaction, there certainly some other more benign things to think of.
The first thing people think of with the right lower quadrant is related to the appendix. Depending on the scan you had (contrast or not), they may have also been able to rule out diverticulosis
(which may or may not hurt, and if becomes infected is called diverticulitis
). Depending on age and risks, you could have a blockage in the gut. Sometimes people present to me with these symptoms and are just simply constipated (but -- that's a diagnosis i'd only make after an extensive evaluation of the other things i've listed here).
I've had patients with gall bladder problems
present with right lower abdominal pain
and ct scans aren't sensitive enough to make that diagnosis for some reason. You should also consider ulcer disease.
So, lots to consider , but i think the safest thing to do is get back with your doctor as soon as you can.
Good luck to you!