IBS? Colon Cancer? Something else?

Since you have only had this problem for 5 days it is almost impossible to say what it might be. It sounds as if your diet lacks sufficient fiber. If you dislike eating vegetables, purchase a fiber supplement like Benefiber or Citricel. Statrt upping your fiber a little at a time so as not to give yourself additional problems. Your stools are likely thin because they lack bulk which is provided by fiber. Also, a lack of fiber can cause constipation.

If you are concerned you have a disease like cancer, you should visit your doctor. I'm betting if you get your constipation under control, you will see an improvement.