[rawhide]

Gall Bladder is located on the right side (I had mine removed).
OP said his pain is on the left side, below the rib cage.
So it is not the gall bladder.

[freekitty]

I had pain in different spots.

[ErnBatavia]

I had my gallbladder yanked just over a year ago....the discomfort could be anywhere in the upper gut area depending on the “attack”. Fortunately, a simple ultrasound nailed the cause.