I am not a doctor but two of your symptoms did stand out to me. I wanted to comment based on my own health experiences.
Frequent thirst is often a symptom of Diabetes. As part of you lab work make sure you have a fasting blood sugar test as well as a test called an HBA1C. These two tests indicate how your body is utilizing insulin to regulate blood glucose levels.
The sudden sharp pain underneath the left part of you body by your ribs could indicate problems with your gall bladder. Those are similar symptoms I had and then had to have my gall bladder removed.
Holding off running would be a good idea until you get an accurate diagnosis and effective treatment plan from your doctor.
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