As an ex RN anything one-sided is either an organ or damage to the other side of the brain. Could it be your spleen? Spleen problems aren't rare and they can cause pain on your left side and under your left rib. Ironically, I now have an enlarged spleen but doc didn't know why & my platelets ( connected to your spleen) have been slightly low for some time. It could also be your kidney. If you've already had these organs tested for disease, inflammation or infection, it may be the nerves that are effected. Nerve pain is hard to diagnose and treat. Good luck in your search for answers. It can take some time to find a good doctor willing to try to get to the root of your pain.

I don't think they ever tested my spleen or kidney... I'm definitely going to mention that. I had a doctor recently (unrelated to the side pain) mention that it might be a good idea to see a nephrologist due to my hypertension being diagnosed so young... I guess this is another sign. So far, they've treated it as nerve pain after checking the gallbladder/GI system. It's helped a little but not much.

Thank you so much by the way!