Hello I am 16 and lately I have been having stomach ach, mainly at the bottom and both sides of the lower abdominals . On top of that, I ve been sweating a lot during the day, right until the night and cannot sleep at all. When do I try to sleep, I feel a bit of pressure on the side of my lower abdominal. Lastly, I have a black stool each time I take the trip to the loo. I think this might be due to sitting on the coach all day and the lack of sleep. Also the late heavy snacks which I eat during the night. Although perhaps knowing what the causes are due to my problems, I just like to make sure. So could you help me. Thanks