Hi, I started with dull pain upper left stomach, that got worse. It was waking me up at night. Also headaches and now after I eat, I get so nauseous. My bowl movements change constatntly, from constipation to diarrhea. I have noticed that in my diarrhea I have what looks like black sand. What could be going on. In January I had a total hysterectomy and diagnosed with stage 1 ovarian cancer, went through few chemo sessions.