The stool is dark brown and somewhat lumpy, corresponding to Bristol type 2. Consider increasing fiber intake to soften the stool. Consult with a doctor if IBS symptoms worsen.

The stool corresponds to type 2 on the Bristol Stool Scale and has a very dark brown color. It's recommended to increase water intake and consume a diet rich in fiber to prevent constipation. Since you have IBS, pay extra attention to your diet.