Why Am I Passing Yellow Stool?

i've been having yellow stool for about six weeks. i've had acid reflux symptoms too, and i know this can cause yellow stool, but even when i don't use the bathroom for a full twenty-four hours the stool is still coming out yellow, which seems to me not to be related to gerd. i know it could be a gallbladder, pancreas, or liver issue, and this is scaring me. i'm a forty year old male, otherwise healthy, who exercises and eats right. any advice other than to see my doctor. i'm scheduled with a gi in three weeks, and i'm wondering if this is too long to wait.