Hi, about 2 months ago I was sick for about 12 hours with chronic stomach pain and also constant vomitting and watery diahrea. Ever since I havent been able to eat right. I get full after the first couple of bites that I take from my meal. I have lots of weight loss now weighing about 85-90 pounds. Recently I have been having a problem with my stool, it is a very dark to black color. Should I be concerned?