I have been feeling lightheaded last two days. This Am my stool had blackish parts to it, but was not smelly. I have been eating blueberries, but also recently recovered from a serious duodenal ulcer, who healed about three weeks ago. I have returned to taking mobic for arthritis/one per day with food. My gastroenterologist is not in today, my internist has not responded to my call yet. Does this sound like an emergency room situation, or one that can wait to see the Dr tomorrow?