Increased alkaline phosphatase

I have pain on my left side of the abdomen, under the rib cage and sometimes radiating to the back and down to the lower colon, for a period of about 12 months. I had a CT Contrast Scan - twice in 6 months, nothing showed up.  Then I had a routine blood test in Dec for a routine cholesterol and liver level check and my ALP was at 90, which normally was lower than that.  Retested two weeks later and it was 130, then went to a gastroenterologist who ordered a battery of blood tests and they came back with alkaline phosphatase level of 616.  I just took another blood this morning to check the alkaline phosphatase isoenzyme for primary bile duct problems and gallbladder disease.  My liver and my gallbladder are on the right side so I have to wonder why my left side hurts so much if they're checking for right side issues.  I feel absolutely great, except for the left side pain, not yellow, no issues with my stool or urine.  Do you have any thoughts on why the alkaline phosphatase level being so high - can it be related to GERD?  I started eating apples and drinking apple juice because I read that it clears the bile ducts, but that just made my right side hurt even more.  I'm 62 and tired of the aches and pains.